A free course management system (CMS) to create online learning sites
Moodle is a Course Management System (CMS), also known as a Learning Management System (LMS) or a Virtual Learning Environment (VLE). It is a Free web application that educators can use to create effective online learning sites. https://moodle.org/
A partition and disk imaging/cloning program
Clonezilla is a partition and disk imaging/cloning program similar to True Image®. It saves and restores only used blocks in hard drive. Two types of Clonezilla are available, Clonezilla live and Clonezilla SE (Server Edition).
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.
RetroShare is a cross-platform, secured and decentralized communication system. It lets you to securely chat, share photos, videos, and more with family and friends, using OpenPGP to authenticate peers and OpenSSL to encrypt all communication.
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.
A graphical network simulator to design and configure virtual networks
GNS3 is a graphical network simulator that allows you to design complex network topologies. You may run simulations or configure devices ranging from simple workstations to powerful Cisco routers. It is based on Dynamips, Pemu/Qemu and Dynagen. Go to GNS3.com for last releases.
phpSysInfo is a customizable PHP Script that parses /proc, and formats information nicely. It will display information about system facts like Uptime, CPU, Memory, PCI devices, SCSI devices, IDE devices, Network adapters, Disk usage, and more.
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.
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.
Geany is a small and lightweight integrated development environment. Basic features are syntax highlighting, code completion, code folding, call tips, many supported filetypes.
BackupPC is a high-performance, enterprise-grade backup system for backing up Linux, WinXX PCs, Macs and laptops to a server's disk. Features include clever pooling of identical files, no client-side software, and a powerful Apache/CGI user interface.
eAccelerator is a further development from mmcache PHP Accelerator & Encoder. It increases performance of PHP scripts by caching them in compiled state, so that the overhead of compiling is almost completely eliminated.
Rapid applications development tool and libraries for FPC
The Lazarus IDE is a stable and feature rich visual programming environment for the FreePascal Compiler. It supports the creation of self-standing graphical and console applications and runs on Linux, FreeBSD, MacOSX and Windows.
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.
An intuitive molecular editor and visualization tool
Avogadro is an advanced molecular editor designed for cross-platform use in computational chemistry, molecular modeling, bioinformatics, materials science and related areas. It offers a flexible rendering framework and a powerful plugin architecture.
A Jump and Run game like Super Mario World with an advanced Editor and highly detailed Graphics based on SDL with a OpenGL accelerated Graphics Renderer developed in C++. Runs under Linux, Windows and Mac and can be easily ported to other platforms.
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.
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.
Audio Tag Editor
Kid3 audio tag editor can edit the tags of MP3, Ogg, FLAC, MPC & WMA files in an efficient way, convert between ID3v1 and ID3v2, set the tags of multiple files, generate tags from file names or vice versa and import from freedb, MusicBrainz and Disco
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.
A tool for learning programming basis with a simple spanish pseudocode
PSeInt is a pseudo-code interpreter for spanish-speaking programming students. Its main purpose is to be a tool for learning and understanding the basic concepts about programming and applying them with an easy understanding spanish pseudocode.
Xfce is an easy-to-use and easy-to-configure desktop environment using the popular GTK+ toolkit.
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.
Modular, touch screen friendly navigation system with GPS tracking, realtime routing engine and support for various vector map formats. Works on a wide range of devices, from computers to smartphones.