GCompris is an educational software suite with numerous activities for children aged 2 to 10. Some of the activities are game-orientated, but nonetheless still educational. These include computer discovery (keyboard, mouse, different mouse gestures), algebra (table memory, enumeration, double entry table, mirror image), science (the canal lock, the water cycle, the submarine, electric simulation), geography (place the country on the map), games (chess, memory, connect 4, oware, sudoku), reading practice, and others (learn to tell time, puzzles of famous paintings, vector drawing, cartoon making, etc.). It currently offers in excess of 100 activities, and more are being developed.
Gravit is a gravity simulator. It uses Newtonian physics using the Barnes-Hut N-body algorithm. Although the main goal of Gravit is to be as accurate as possible, it also creates beautiful looking gravity patterns. It records the history of each particle so that it can animate and display a path of its travels. At any stage you can rotate your view in 3D and zoom in and out. Gravit uses OpenGL, Lua, SDL, SDL_ttf, and SDL_image.
Dyne:bolic GNU/Linux is a live bootable operating system equipped with a wide range of multimedia applications: editors and streamers of audio and video, 3D modelers, image processors, P2P file-sharing tools, Web browsers, an office suite, and full encryption of storage and communication. Dyne:bolic is optimized to run on old computers, runs the Linux-Libre kernel, and omits all non-free software. It can be well used without a network connection, and it comes with all the tools and libraries needed to customize the OS.
Guitar Trainer is an application for mobile devices that helps musicians learn the fretboard of their stringed instrument thoroughly. It supports guitar, bass, banjo, ukulele, mandolin, and cavaquinho (in standard and alternate tunings). It includes a training mode, a game mode, and a tuner. It should work on any Java device supporting CLDC 1.1/MIDP 2.0.
Homemade Dictionary is a customizable and easy to use dictionary, with features including background music support. It has a built in "Test Your Word Power Game", a medical dictionary, and a superb GUI. The dictionary has an initial database of of around 5900 words, including slang. You may also add your personal words on the fly. It is very small in size (around 700 KB).
Asymptopia Crossword Builder (Math/Text) is an application that runs in any modern Web browser, but does not require an Internet connection (if it is installed locally). The application was designed to allow teachers to quickly produce well-designed, challenging activities. The application features a configuration panel where the user can either enter their own word-hint pairs, or generate math-crossword problems via a single button. The math functionality generates word:hint pairs like: "four:7/x-3/8=11/8", where the hint corresponds to the problem, and the student would write the letters "four" in the corresponding boxes of the puzzle.