f/Calc is a utility to calculate lens formulae for photographers so you can focus on the artistic bits rather than on the mathematics behind it all. f/Calc can do "f" number arithmetic, and can calculate depth of field, hyperfocal distance, the field of view of a lens, the angle of view of a lens, magnification, and how the focal length of the lens on the camera changes the way the spot metering function works. In addition to the Unix/Linux Tcl/Tk version, there are native Windows, Palm OS, and Macintosh versions as well.
FIDOGATE is a Fido-Internet gateway and a Fido tosser. The gateway converts between the worlds of Fido NetMail/EchoMail (or FTNs, Fido Technology Networks in general) and the UNIX mail/news system. FIDOGATE will convert Fido mail packets to RFC822/1036-style messages and vice versa.
Freeciv is a multiuser reimplementation for Unix/X of the famous Microprose game of Civilization. By default, the game is an improved Civ II, but this can be customized; modpacks for near-100% compatibility with Civ I and Civ II are included. Multiuser gameplay is real-time: in each turn, all human players move concurrently. The game is designed to remain fairly playable even on poor network connections. Freeciv can also be played on standalone machines, and its AI players are a good challenge for beginners. The source code comes with the server, two X clients, and non-X clients for MS Windows and Amiga. Freeciv is released under the GNU General Public License. It is maintained by an international team of coders and enthusiasts, and is easily one of the most fun and addictive network games out there.
Freemed-YiRC is a PHP package based on Freemed for use with Youth in Residential Care (YiRC) agencies. Its aim is to be a complete package to replace legacy non-free apps which aren't customizable. Since it's PHP-based, all that is needed for the client is a good Web browser with extensive table support. Some of the objectives for Freemed-YiRC are: User Management, a Contact Database, Clinical CaseNotes, an Incident Report System, an email client, a Service Plan System, a Timecard System, and Medical Billing (Medicaid/Insurance/Private).
Fugu is a standalone, graphical client for the Gale instant messaging system. It is fully featured and supports all common Gale messaging operations. In addition, Fugu features a Windows port, multiple screens for different subscription lists, clickable URLs, thumbnail pictures showing the sender of each message, and configurable notification when new puffs arrive.
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.