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.
Linux firewall distribution geared towards home and SOHO users.
The IPCop Firewall is a Linux firewall distribution. It is geared towards home and SOHO users. The IPCop web-interface is very user-friendly and makes usage easy.
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.
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 graphical text difference analyzer
KDiff3 is a graphical text difference analyzer for up to 3 input files, provides character-by-character analysis and a text merge tool with integrated editor. It can also compare and merge directories. Platform-independant.
Windows installer development tool
NSIS (Nullsoft Scriptable Install System) is a professional open source system to create Windows installers. It is designed to be as small and flexible as possible and is therefore very suitable for internet distribution. Being a user's first experience with your product, a stable and reliable installer is an important component of succesful software. With NSIS you can create such installers that are capable of doing everything that is needed to setup your software. NSIS is script-based and allows you to create the logic to handle even the most complex installation tasks. Many plug-ins and scripts are already available: you can create web installers, communicate with Windows and other software components, install or update shared components and more.
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/
Panorama photo stitcher
With Hugin you can assemble a mosaic of photographs into a complete immersive panorama, stitch any series of overlapping pictures and much more.
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.
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.
a parametric 3D CAD modeler
WARNING: FreeCAD has moved! FreeCAD code and release files are now hosted on github at https://github.com/FreeCAD/FreeCAD Only older files and code are available here. FreeCAD is a general purpose feature-based, parametric 3D modeler for CAD, MCAD, CAx, CAE and PLM, aimed directly at mechanical engineering and product design but also fits a wider range of uses in engineering, such as architecture or other engineering specialties. It is 100% Open Source and extremely modular, allowing for very advanced extension and customization. FreeCAD is based on OpenCasCade, a powerful geometry kernel, features an Open Inventor-compliant 3D scene representation model provided by the Coin 3D library, and a broad Python API. The interface is built with Qt. FreeCAD runs exactly the same way on Windows, Mac OSX and Linux platforms.
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.
A very efficient tutor.
A touch typing tutor very flexible, supporting customizable keyboard layouts. You can edit and save new or unknown keyboard layouts, as the basic course was designed to not depend on specific ones. Also, there are some charts about the learning process.
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.
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
OpenEMR is an open source medical practice management application (EHR EMR PMS) featuring fully integrated electronic health records, scheduling, electronic billing, internationalization, free support, a vibrant community, and a whole lot more.
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.
KGB Archiver is the compression tool with unbelievable high compression rate. It surpasses even such efficient compression tool like 7zip and UHARC in terms of the abilities. KGB Archiver uses AES-256 encryption to encrypt archives.
Free Zip software and Rar extractor
PeaZip is a free archiver tool. The application provides an unified, natively portable, cross-platform file manager and archive manager GUI for many Open Source technologies like 7-Zip, FreeArc, PAQ, UPX. Create: 7Z, ARC, BZip/GZip, PEA, TAR, WIM, XZ, ZPAQ, ZIP files and more Open and extract 180+ file types: ACE, CAB, DEB, ISO, RAR, ZIPX and more Features of PeaZip includes extract, create and convert multiple archives at once, create self-extracting archives (sfx), split files, strong encryption with two factor authentication, encrypted password manager, secure deletion, find duplicate files, calculate hashes, export task definition as command line script. ACE file extraction needs separate installation of free (but not Open Source, due original format licensing restrictions) UNACE Plugin, available on Add-ons page of PeaZip website. Due the closed-source nature of this component, it has been separated from the main package, which contains only Open Source components.
Real-time 3D visualization of space
Celestia is an application for real-time 3D visualization of space, with a detailed model of the solar system, over 100,000 stars, more than 10,000 galaxies, and an extension mechanism for adding more objects.
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.