Open Source desktop project management
OpenProj is an open-source desktop project management application similar to Microsoft Project. OpenProj has a familiar user interface and even opens existing MS Project files. OpenProj is interoperable with Project, Gantt Charts and PERT charts.
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.
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).
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.
Enterprise-class, distributed monitoring solution for networks & apps
ZABBIX is an enterprise-class open source distributed monitoring solution designed to monitor and track performance and availability of network servers, devices and other IT resources. It supports distributed and WEB monitoring, auto-discovery, and more. An enterprise-class distributed monitoring solution for networks & apps
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.
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 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.
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.
Computer Algebra System written in Common Lisp
Maxima is a computer algebra system comparable to commercial systems like Mathematica and Maple. It emphasizes symbolic mathematical computation: algebra, trigonometry, calculus, and much more. For example, Maxima solves x^2-r*x-s^2-r*s=0 giving the symbolic results [x=r+s, x=-s]. Maxima can calculate with exact integers and fractions, native floating-point and high-precision big floats. Maxima has user-friendly front-ends, an on-line manual, plotting commands, and numerical libraries. Users can write programs in its native programming language, and many have contributed useful packages in a variety of areas over the decades. Maxima is GPL-licensed and largely written in Common Lisp. Executables can be downloaded for Windows, Mac, Linux, and Android; source code is also available. An active community maintains and extends the system. Maxima is widely used: annual direct downloads exceed 300,000. Many other users receive it through secondary distribution.
A cross-platform statistical package for econometric analysis
gretl is a cross-platform software package for econometric analysis, written in the C programming language.
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.
An enterprise-class CRM and more!
Vtiger CRM enables sales, support, and marketing teams to organize and collaborate to measurably improve customer experiences and business outcomes. Vtiger CRM also includes email, inventory, project management, and other tools, providing a complete the business management suite. Download Vtiger CRM here or sign up for a free 15-day free trial of the cloud-based application with free updates and support at https://www.vtiger.com/
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 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
the virtual reality authoring toolkit that was created for artists
Jahshaka is bringing you the future of immersive digital content creation. It combines a virtual desktop with a powerful asset management system and a immersive 3d content creation engine with full VR support. Jahshaka is free software, developed as an open source project and is designed to run on Windows, OsX and Linux.
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.
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.
Domination is a game that is a bit like the well known board game of Risk or RisiKo. It has many game options and includes many maps. Written in java it includes a map editor, a simple map format, multiplayer network play, single player, hotseat, 5 user interfaces and many more features, it works in all OSs that run java 1.4 or higher, and Android.
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.