A free multi-track audio editor and recorder
Audacity is a free, easy-to-use, multi-track audio editor and recorder for Windows, Mac OS X, GNU/Linux and other operating systems. The interface is translated into many languages. The version currently hosted here is 2.1.0 (March 2015). More recent versions than this are available from http://www.audacityteam.org/download/ . Audacity is free software, developed by a group of volunteers and distributed under the GNU General Public License (GPL). Programs like Audacity are also called open source software, because their source code is available for anyone to study or use. There are thousands of other free and open source programs, including the Firefox web browser, the LibreOffice or Apache OpenOffice office suites and entire Linux-based operating systems such as Ubuntu
A free and reliable P2P BitTorrent client
An advanced and multi-platform BitTorrent client with a nice Qt user interface as well as a Web UI for remote control and an integrated search engine. qBittorrent aims to meet the needs of most users while using as little CPU and memory as possible.
An award-winning drawing program for children ages 3 to 12
Tux Paint is a free, award-winning drawing program for children ages 3 to 12. It combines an easy-to-use interface, fun sound effects, and an encouraging cartoon mascot who guides children as they use the program. Kids are presented with a blank canvas and a variety of drawing tools to help them be creative. Along with paintbrush, shapes and text, Tux Paint includes a "stamp" feature to add pre-drawn or photographic imagery to pictures, and a set of "magic tools" that provide filter effects (like blur, tint and waves) and interesting drawing tools (like train tracks, bubbles and grass). Tux Paint includes a collection of "starter" images, both coloring-book style and photo-realistic, and a large collections of stamps are available as a separate download. Additional content can be added by parents and teachers, or downloaded from 3rd parties. Tux Paint is available for Linux, BSD, Windows, Mac OS X and Haiku operating systems.
Audio converter and CD ripper for various formats
fre:ac is a free audio converter and CD ripper for various formats and encoders. It features MP3, MP4/M4A, WMA, Ogg Vorbis, FLAC, AAC, and Bonk format support, integrates freedb/CDDB, CDText and ID3v2 tagging and is available in several languages.
An extremely powerful and configurable BitTorrent client
Vuze (formerly Azureus) is an extremely powerful and configurable BitTorrent client. Search and download torrent files. Play, convert and transcode videos and music for playing on many devices such as PSP, TiVo, XBox, PS3, iTunes (iPhone, iPod, Apple TV).
A planetarium software that shows a 3D simulation of the night sky
Stellarium renders 3D photo-realistic skies in real time with OpenGL. It displays stars, constellations, planets, nebulae and others things like ground, landscape, atmosphere, etc.
Streams many media formats with minimal configuration
Universal Media Server is a DLNA-compliant UPnP Media Server Universal Media Server supports all major operating systems, with versions for Windows, Linux and Mac OS X. The program streams or transcodes many different media formats with little or no configuration. UMS is powered by MEncoder, FFmpeg, tsMuxeR, AviSynth, MediaInfo and more, which combine to offer support for a wide range of media formats Check out the list of media renderers here: http://www.universalmediaserver.com/about/
A free transportation simulator game
Simutrans is a cross-platform simulation game where players try to successfully manage transportation systems between places by land, air, and water for passengers, mail, and goods. Planes, ships, trains, trams, trucks, buses, or monorails are at your disposal, but factories operate based on contracts and passengers can only travel to their set destinations.
Open source erp and crm web software for business
Dolibarr ERP - CRM is an easy to use ERP and CRM open source software package (run with a web php server or as standalone software) for businesses, foundations or freelancers (prospect, invoicing, inventory, warehouse, order, shipment, POS, members for foundations, bank accounts...). Dolibarr is also available with auto-installers for users with no technical knowledge to install Dolibarr and all its prerequisites (Apache, Mysql, PHP) with just one package. Available platforms for such packages are: Windows, Debian, Ubuntu, Mint, Redhat, Fedora, OpenSuse, Mandriva, Mageia. Other platform can use the generic distribution. This is a modular product, than can be enhanced with tons of external modules (to provide you features not available by default) from https://www.dolistore.com Download Dolibarr ERP - CRM here or sign up for 15-day free trial of the cloud-based application with free updates and support at one of the Cloud providers https://saas.dolibarr.org/
A universal instant messaging (IM) program
See https://pidgin.im/about/ for more information. Pidgin is an instant messaging program which lets you log in to accounts on multiple chat networks simultaneously. It runs on Windows, Linux, and other UNIX operating systems. Pidgin is compatible with the following chat networks out of the box: AIM, ICQ, Google Talk, Jabber/XMPP, MSN Messenger, Yahoo!, Bonjour, Gadu-Gadu, IRC, MXit, Novell GroupWise Messenger, Lotus Sametime, SILC, SIMPLE, MySpaceIM, and Zephyr. It is written in C and makes heavy use of GLib and GTK+. Finch is a command line instant messaging program. It also lets you log in to accounts on multiple chat network simultaneously, and it is compatible with the same chat networks as Pidgin. It is written in C and makes heavy use of GLib and ncurses.
RTS game with the theme of Strategy by Design
You command the forces of “The Project” in a battle to rebuild the world after mankind has almost been destroyed by nuclear missiles. The game offers a full campaign with optional (but strongly recommended!), videos, battle against four factions, multi-player and single-player skirmish modes, and an extensive tech tree and a full unit designer. Multi-player is also cross-platform, battle your friends with any OS, Windows, Linux or Mac, it all works seamlessly! We also offer 100% portable Windows builds, take the game and install it anywhere! Our source repo is now at https://github.com/Warzone2100/warzone2100 If you are using linux, and want a .deb, then please get the latest version available from http://www.playdeb.net/app/Warzone2100 (They are not affliated with us, but they do have the latest builds!) Warzone 2100 works on both 32 & 64 bit Windows Vista or higher, 32 or 64 bit Linux, 32 or 64 bit Macs.
Run Windows applications on Linux, BSD, Solaris, and Mac OS X
Wine is an Open Source implementation of the Windows API on top of X and Unix. Wine provides both a development toolkit for porting Windows sources to Unix and a program loader, allowing many unmodified Windows binaries to run on x86-based Unixes.
gPhoto is a program and library framework that lets users download pictures from their digital cameras. The libgphoto2 library gives you access to hundreds of models of digital cameras on several platforms. GIT repo and Issue tracker lives at https://github.com/gphoto/ these days.
A very high quality package of printer drivers for CUPS on Linux, Macintosh OS X, and other POSIX-compliant operating systems. This project also maintains an enhanced Print plug-in for GIMP 2.x from the same code base.
A cross-platform GUI library
wxWidgets is a C++ library that lets developers create applications for Windows, Mac OS X, Linux and other platforms with a single code base. It has popular language bindings for Python, Perl, Ruby and many other languages, and unlike other cross-platform toolkits, wxWidgets gives applications a truly native look and feel because it uses the platform's native API rather than emulating the GUI. It's also extensive, free, open-source and mature.
A free sing-along karaoke game for your PC
Karaoke sing-along game for PC which is similar to Playstation® Singstar™. It allows up to six players to sing along with music using microphones in order to score points, depending on the pitch of the voice and the rhythm of singing.
AWStats is a free powerful and featureful server logfile analyzer that shows you all your Web/Mail/FTP statistics including visits, unique visitors, pages, hits, rush hours, os, browsers, search engines, keywords, robots visits, broken links and more
Synfig is a powerful, industrial-strength vector-based 2D animation software package, designed from the ground-up for producing feature-film quality 2D animation with fewer people and resources.
smart and open source document management system
LogicalDOC is both document management and collaboration system. The software is loaded with many functions and allows organizing, index, retrieving, controlling and distributing important business documents securely and safely for any organization and individual. Gone are the days when companies used paper-based processes such as printing, mailing and manual filing of paper documents; our document management system replaces all of this with electronic procedures that allow your organization to reduce costs significantly. Check out https://www.logicaldoc.com to learn more. The design of LogicalDOC is based on best-of-breed Java technologies in order to provide a reliable DMS platform. The main interface is web-based, no need to install anything else; users can access the system through their browser. LogicalDOC CE is 100% free software and is packaged with an open source database; while it supports all major DBMS, developers still recommend MySQL for production systems.
Free church worship presentation software
Open Source Worship Presentation Software. This project has moved to Launchpad: https://launchpad.net/openlp
A 3D simulator game where you can drive, fly, and sail
Rigs of Rods is a 3D simulator game where you can drive, fly and sail various vehicles using an accurate and unique soft-body physics engine. Since 2014, the development continued at https://github.com/RigsOfRods/rigs-of-rods UPDATE: 10/30/2016: removed opencandy installers, replaced with zip files.
Cross platform GUI for Maxima
wxMaxima is a cross-platform graphical front-end for the computer algebra system Maxima based on wxWidgets. It provides nice display of mathematical output and easy access to Maxima functions through menus and dialogs.
"Tux, of Math Command" is a math drill game starring Tux, the Linux Penguin. Lessons are included from simple number typing through addition, subtraction, multiplication, and division of positive and negative numbers. It is intended for kids ~4-10.
Free music notation & composition software
MuseScore is the leading free & open source music notation software for Windows, Mac and Linux. It is easy to use and makes beautiful sheet music. MuseScore is often praised as a cost effective alternative for Sibelius and Finale. Support MuseScore at http://musescore.org/en/donate Like MuseScore on Facebook: http://facebook.com/musescore
Bluefish is a powerful editor for experienced web designers and programmers. Bluefish supports many programming and markup languages, but it focuses on editing dynamic and interactive websites.