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Open Source Software for Windows

Games :: Cube

3D Rendered First Person Shooter.
Cube 1 is better for for lower spec machines. Cube 2 is for higher-end equipment and is also known as Sauerbraten.

From the Cube Website:

Cube is an open source multiplayer and singleplayer first person shooter game built on an entirely new and very unconventional engine. Cube is a landscape-style engine that pretends to be an indoor FPS engine, which combines very high precision dynamic occlusion culling with a form of geometric mipmapping on the whole world for dynamic LOD for configurable fps & graphic detail on most machines. Uses OpenGL & SDL.

Allows in-engine editing of geometry in full 3D (you fly around the map, point / drag stuff to select it / modify it), which can even be done simultaneously with others in multiplayer (a first!). Has simplistic but effective fine grain vertex lighting that looks like lightmapping and can do dynamic lights & shadows. Doesn't need any kind of map precompilation, even lighting is done on the fly. Has very simplistic quad-tree world structure that can do slopes (heightfields with caps) and slants, water, does decent collision detection & physics, has client/server networking that goes a long way in giving a lag-free game experience, and features a Doom/Quake-style singleplayer (2 game modes, savegames) and multiplayer (12 game modes, master server / server browser, demo recording) game with some uncompromising brutal oldskool gameplay.
Games :: Nexuiz

3D Rendered First Person Shooter.
From the Nexuiz Website:

Nexuiz is a fast paced 3D deathmatch game project created online by a team of developers called Alientrap. It is available for download for Windows, Mac, and Linux (all the same archive).

The first version was released May 31st 2005, released entirely GPL and free over the net, a first for a project of its kind. Since then it has been downloaded over 1.5 million times, and the game is still being updated and developed, currently at version 2.4 and new releases being developed.
Desktop Publishing :: Scribus From the Scribus Website:

Scribus is an open-source program that brings award-winning professional page layout to Linux/Unix, MacOS X, OS/2 and Windows desktops with a combination of "press-ready" output and new approaches to page layout.

Underneath the modern and user friendly interface, Scribus supports professional publishing features, such as CMYK color, separations, ICC color management and versatile PDF creation.
CD Ripper :: CDex
From the CDex Website:

CDex can extract the data directly (digital) from an Audio CD, which is generally called a CD Ripper or a CDDA utility. The resulting audio file can be a plain WAV file (useful for making compilation audio CDs) or the ripped audio data can be compressed using an audio encoder. Many encoders are supported, to name a few:
  • Lame MP3 encoder
  • Internal MP2 encoder
  • APE lossles audio format
  • Ogg Vorbis encoder
  • The Windows MP3 encoder (Fraunhofer MP3 encoder)
  • NTT VQF encoder
  • FAAC encoder
  • Windows WMA8 encoder
In addition, WAV files on the hard drive can be converted to a Compressed Audio File (and visa versa). CDex also supports many audio file tag formats like the ID3V1 and ID3V2 tags, which can be automatically inserted as part of the ripping process.
DVD Authoring :: DVD Flick
From the DVD Flick Website:

DVD Flick aims to be a simple but at the same time powerful DVD Authoring tool. It can take a number of video files stored on your computer and turn them into a DVD that will play back on your DVD player, Media Center or Home Cinema Set. You can add additional custom audio tracks as well as subtitles of your choice.
  • Burn almost any video file to DVD
  • Support for over 45 file formats
  • Support for over 60 video codecs
  • Support for over 40 audio codecs
  • Add your own subtitles
  • Easy to use interface
  • Burn your project to disc after encoding
  • Completely free without any adware, spyware or limitations
DVD Authoring :: DVDStyler From the DVDStyler Website:

DVDStyler is a cross-platform DVD authoring application that makes possible for video enthusiasts to create professional-looking DVDs. It is Free software distributed under the GNU General Public License (GPL).
  • Drag and drop MPEG files directly
  • Create NTSC/PAL menus
  • Import image file for background
  • Place text and images anywhere on the menu screen
  • Change font/color
  • Put buttons, change font and colors
  • Copy and paste any menu object
  • Set chapters for each movie
  • Change post command for each movie
CD/DVD Burner :: InfraRecorder
From the InfraRecorder Website:

InfraRecorder is a free CD/DVD burning solution for Microsoft Windows. It offers a wide range of powerful features; all through an easy to use application interface and Windows Explorer integration. InfraRecorder is released under GPL version 2.
  • Create custom data, audio and mixed-mode projects and record them to physical discs as well as disc images.
  • Supports recording to dual-layer DVDs.
  • Erase rewritable discs using four different methods.
  • Record disc images (ISO and BIN/CUE).
  • Fixate discs (write lead-out information to prevent further data from being added to the disc).
  • Scan the SCSI/IDE bus for devices and collect information about their capabilities.
  • Create disc copies, on the fly and using a temporary disc image.
  • Import session data from multi-session discs and add more sessions to them.
  • Display disc information.
  • Save audio and data tracks to files (.wav, .wma, .ogg, .mp3 and .iso).
Media Player :: VideoLAN - VLC From the VideoLAN Website:

VideoLAN produces free software for video, released under the GNU General Public License. It started as a student project at the French École Centrale Paris but is now a worldwide project with developers from 20 countries.
  • Complete list of features (extensive)
  • Supports DVB (Satellite, Digital TV & Cable TV)
  • Supports a large number of multimedia formats, without the need for additional codecs
  • Can also be used as a streaming server, with extended features (video on demand, on the fly transcoding)
Typing Tutor :: Tux Typing
From the Tux Typing Website:

"Tux Typing" is an educational typing tutor for children. It features several different types of gameplay, at a variety of difficulty levels.
Audio Editor :: Audacity From the Audacity Website:

Audacity® is a free, easy-to-use audio editor and recorder for Windows, Mac OS X, GNU/Linux, and other operating systems. You can use Audacity to:
  • Record live audio
  • Convert tapes and records into digital recordings or CDs
  • Edit Ogg Vorbis, MP3, and WAV sound files
  • Cut, copy, splice, and mix sounds together
  • Change the speed or pitch of a recording
  • Dub over existing tracks to create multi-track recordings
  • Import sound files, edit them, and combine them with other files or new recordings.
  • Export your recordings in several common file formats And more.
  • Full list of features.
Media Conversion :: MediaCoder
MediaCoder is a free universal audio/video batch transcoder, putting together lots of excellent audio/video codecs and tools from the open source community into an all-in-one solution, capable of transcoding among different audio/video formats with many extra features:
  • Improve compression & reduce file size
  • Convert from lossless/high-bitrate audio to low-bitrate audio to play with portable DAP
  • Convert to device (mobile phone, PDA, MP4 player, PSP, VCD/DVD player)
  • Extract audio tracks from video clips Ripping CD/VCD/DVD
Music Tutor :: Jalmus
From the Jalmus Website:

Jalmus is a free, open source music education software helping the musicians, especially pianists, to improve their sight-reading. You can train to read music with both exercises on notes or rhythms.

Jalmus is developed in Java and so available on Microsoft Windows, Linux and Mac OS. Jalmus is multilingual software, supporting English, French, Spanish, Italian, Danish and German.
Graphics Editor :: paint.NET
From the paint.NET Website:

Simple, intuitive, and innovative user interface
Every feature and user interface element was designed to be immediately intuitive and quickly learnable without assistance. In order to handle multiple images easily, Paint.NET uses a tabbed document interface. The tabs display a live thumbnail of the image instead of a text description. This makes navigation very simple and fast.

Layers
Usually only found on expensive or complicated professional software, layers form the basis for a rich image composition experience. You may think of them as a stack of transparency slides that, when viewed together at the same time, form one image.

Active Online Community
Paint.NET has an online forum with a friendly, passionate, and ever-expanding community. Be sure to check out the constantly growing list of tutorials and plugins!

Frequently Updated
Updates usually come about every 4 to 6 weeks, and contain new features, performance improvements, and bug fixes. Upgrading to the latest version is very simple, requiring only two clicks of the mouse.

Special Effects
Many special effects are included for enhancing and perfecting your images. Everything from blurring, sharpening, red-eye removal, distortion, noise, and embossing are included. Also included is our unique 3D Rotate/Zoom effect that makes it very easy to add perspective and tilting.

Adjustments are also included which help you tweak an image's brightness, contrast, hue, saturation, curves, and levels. You can also convert an image to black and white, or sepia-toned.

Powerful Tools
Paint.NET includes simple tools for drawing shapes, including an easy-to-use curve tool for drawing splines or Bezier curves. The Gradient tool, new for 3.0, has been cited as an innovative improvement over similar tools provided by other software. The facilities for creating and working with selections is powerful, yet still simple enough to be picked up quickly. Other powerful tools include the Magic Wand for selecting regions of similar colour, and the Clone Stamp for copying or erasing portions of an image. There is also a simple text editor, a tool for zooming, and a Recolor tool.

Unlimited History
Everybody makes mistakes, and everybody changes their mind. To accommodate this, every action you perform on an image is recorded in the History window and may be undone. Once you've undone an action, you can also redo it. The length of the history is only limited by available disk space.
Mind Mapping :: FreeMind

Note: FreeMind requires the Java Runtime Environment (JRE). You can obtain the JRE from Sun Microsystems.
From the FreeMind Website:

FreeMind - free mind mapping software

FreeMind is a premier free mind-mapping software written in Java. The recent development has hopefully turned it into high productivity tool. We are proud that the operation and navigation of FreeMind is faster than that of MindManager because of one-click "fold / unfold" and "follow link" operations.

So you want to write a completely new metaphysics? Why don't you use FreeMind? You have a tool at hand that remarkably resembles the tray slips of Robert Pirsig, described in his sequel to Zen and the Art of Motorcycle Maintenance called Lila. Do you want to refactor your essays in a similar way you would refactor software? Or do you want to keep personal knowledge base, which is easy to manage? Why don't you try FreeMind? Do you want to prioritize, know where you are, where you've been and where you are heading, as Stephen Covey would advise you? Have you tried FreeMind to keep track of all the things that are needed for that?
Psychedelia :: electric sheep

Highly recommended by kadaitcha.cx. The application is a psychedelic screensaver that also creates movie files, which you can replay or edit. It also communicates with other electric sheep users over the Internet to exchange and morph 'sheep'. Recommended for always on, broadband only. If you intend to use the images or movies, or their derivatives, read the terms of electric sheep's Creative Commons licence. From the electric sheep website:

Electric Sheep is a free, open source screen saver run by thousands of people all over the world. It can be installed on any ordinary PC or Mac. When these computers "sleep", the screen saver comes on and the computers communicate with each other by the internet to share the work of creating morphing abstract animations known as "sheep". The result is a collective "android dream", an homage to Philip K. Dick's novel Do Androids Dream of Electric Sheep?.

Anyone watching one of these computers may vote for their favorite animations using the keyboard. The more popular sheep live longer and reproduce according to a genetic algorithm with mutation and cross-over. Hence the flock evolves to please its global audience. You can also design your own sheep and submit them to the gene pool.
Planetarium :: Celestia
  • Celestia Website
  • Screenshots (well worth a look)
  • Download Celestia
From the Celestia Website:

Welcome to Celestia... The free space simulation that lets you explore our universe in three dimensions. Celestia runs on Windows, Linux, and Mac OS X.

Unlike most planetarium software, Celestia doesn't confine you to the surface of the Earth. You can travel throughout the solar system, to any of over 100,000 stars, or even beyond the galaxy.

All movement in Celestia is seamless; the exponential zoom feature lets you explore space across a huge range of scales, from galaxy clusters down to spacecraft only a few meters across. A 'point-and-goto' interface makes it simple to navigate through the universe to the object you want to visit.

Celestia is expandable. Celestia comes with a large catalog of stars, galaxies, planets, moons, asteroids, comets, and spacecraft. If that's not enough, you can download dozens of easy to install add-ons with more objects.
Archiver :: 7zip
From the 7zip Website:
  • High compression ratio in new 7z format with LZMA compression
  • Supported formats:
    • Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR
    • Unpacking only: RAR, CAB, ISO, ARJ, LZH, CHM, MSI, WIM, Z, CPIO, RPM, DEB and NSIS
  • For ZIP and GZIP formats, 7-Zip provides a compression ratio that is 2-10% better than the ratio provided by PKZip and WinZip
  • Strong AES-256 encryption in 7z and ZIP formats
  • Self-extracting capability for 7z format
  • Integration with Windows Shell
  • Powerful File Manager
  • Powerful command line version
  • Plug-in for FAR Manager
  • Localizations for 69 languages
  • 7-Zip works in Windows 98/ME/NT/2000/XP/Vista
Programmer's Editor :: Notepad++
From the Notepad++ Website:

Notepad++ is a free (free as in "free speech", but also as in "free beer") source code editor and Notepad replacement, which supports several programming languages, running under the MS Windows environment.

This project, based on the Scintilla edit component (a very powerful editor component), written in C++ with pure win32 API and STL (that ensures the higher execution speed and smaller size of the program), is under the GPL Licence.
  • Syntax Highlighting and Syntax Folding
  • WYSIWYG
  • User Defined Syntax Highlighting
  • Auto-completion
  • Multi-Document
  • Multi-View
  • Regular Expression Search/Replace supported
  • Full Drag ‘N' Drop supported
  • Dynamic position of Views
  • File Status Auto-detection
  • Zoom in and zoom out
  • Multi-Language environment supported
    • Chinese, Japanese, Korean, Arabic and Hebrew Windows environments are supported
  • Bookmark
  • Brace and Indent guideline Highlighting
  • Macro recording and playback
PDF :: PDFCreator
From the PDFCreator Website:

PDFCreator is a free tool to create PDF files from nearly any Windows application.

Key Features:
  • Create PDFs from any program that is able to print
  • Security: Encrypt PDFs and protect them from being opened, printed etc.
  • Send generated files via eMail
  • Create more than just PDFs: PNG, JPG, TIFF, BMP, PCX, PS, EPS
  • AutoSave files to folders and filenames based on Tags like Username, Computername, Date, Time etc.
  • Merge multiple files into one PDF
  • Easy Install: Just say what you want and everything is installed
  • Terminal Server: PDFCreator also runs on Terminal Servers without problems
  • And the best: PDFCreator is free, even for commercial use! It is Open Source and released under the Terms of the GNU General Public License.
PDF :: pdftk
From the pdftk Website:

If PDF is electronic paper, then pdftk is an electronic staple-remover, hole-punch, binder, secret-decoder-ring, and X-Ray-glasses. Pdftk is a simple tool for doing everyday things with PDF documents. Keep one in the top drawer of your desktop and use it to:
  • Merge PDF Documents
  • Split PDF Pages into a New Document
  • Rotate PDF Pages or Documents
  • Decrypt Input as Necessary (Password Required)
  • Encrypt Output as Desired
  • Fill PDF Forms with FDF Data or XFDF Data and/or Flatten Forms
  • Apply a Background Watermark or a Foreground Stamp
  • Report on PDF Metrics such as Metadata, Bookmarks, and Page Labels
  • Update PDF Metadata
  • Attach Files to PDF Pages or the PDF Document
  • Unpack PDF Attachments
  • Burst a PDF Document into Single Pages
  • Uncompress and Re-Compress Page Streams
  • Repair Corrupted PDF (Where Possible)
pdftk allows you to manipulate PDF easily and freely. It does not require Acrobat, and it runs on Windows, Linux, Mac OS X, FreeBSD and Solaris.
PDF :: Sumatra PDF

kadaitcha.cx suggests Sumatra PDF as a faster and simpler to use replacement for the slow and over-bloated Adobe PDF reader. From the Sumatra PDF Website:

What is Sumatra PDF?
Sumatra PDF is a slim, free, open-source PDF viewer for Windows.

Why another PDF reader?
Sumatra has a minimalistic design. Simplicity has a higher priority than a lot of features. It's small and starts up very fast.

It's designed for portable use: it's just one file with no external dependencies so you can easily run it from external USB drive.
Freeware :: Media Player :: Winamp

Winamp Media Player isn't Open Source, however it is freely available, which is an excellent price to pay for probably the best all-round video and audio media player around. You won't be disappointed by AOL's Winamp.

From the Website:

Unleash the Power of over 18,000 Online Radio Stations with SHOUTcast Radio

Whatever your tastes are, with over 18,000 Online Radio stations, SHOUTcast Radio - the home of free Online Radio - is bound to have a station for you. Tune-in to thousands of free online radio stations from DJs and broadcasters around the world. Listen to SHOUTcast Online Radio at SHOUTcast.com or launch the Media Library in Winamp and check out SHOUTcast Radio in the Online Services.

Access and Share Your Music and Videos On the Go

Winamp Remote turns your home computer into a streaming server and play your music and videos on the go from any PC web browser, compatible cell phones, and TVs with a connected Wii, Xbox 360, or PlayStation 3. Also, share and discover music and videos with friends. Get Your Music and Videos, When and Where You Want. Go Mobile with Winamp Remote here or launch the Media Library and check out Remote Media.
Freeware :: Burner :: ImgBurn

From the ImgBurn Website:

ImgBurn is a lightweight CD / DVD / HD DVD / Blu-ray burning application that everyone should have in their toolkit.

ImgBurn supports a wide range of image file formats - including BIN, CUE, DI, DVD, GI, IMG, ISO, MDS, NRG and PDI.

It supports Unicode folder/file names, so you shouldn't run in to any problems if you're using an international character set.

ImgBurn supports all the Windows OS's - Windows 95, 98, Me, NT4, 2000, XP, 2003, Vista and 2008 (including all the 64-bit versions). If you use Wine, it should also run on Linux and other x86-based Unixes.

It's a very flexible application with several advanced features that are often lacking in other tools, especially when it comes to burning DVD Video discs. It supports all the latest drives without the need for updates (including booktype / bitsetting / advanced settings on many of the major ones - i.e. BenQ, LiteOn, LG, NEC, Plextor, Samsung, Sony).

There is an image queue system for when you're burning several images (which you can automatically share between multiple drives if you have more than one) and an easy-to-use layer break selection screen for double layer DVD Video jobs. The Automatic Write Speed feature allows you store your favourite burn speed settings on a per 'Media ID' basis, right down to a drive by drive level.