distributed.net is a loosely knit group of computer users from all of the world that is taking up challenges requiring lots of computing power (most notably the RC5, DES, and OGR cracking contests). It is simple to participate in the challenges by downloading and running their client software (which uses idle CPU time to complete its tasks).
e3 is a full-screen, user-friendly text editor with an interface similar to that of either WordStar, Emacs, Pico, Nedit, or vi. It's heavily optimized for size and independent of libc or any other libraries, making it useful for mini-Linux distributions and rescue disks. The assembler version supports Linux, FreeBSD, OpenBSD, NetBSD, Win9x, QNX, Atheos, BeOS, ELKS, and DOS. There is also a separately distributed version written in C which supports some other Unix versions and CygWin. It is also possible to use regular expressions by using child processes like sed. e3 has a built in arithmetic calculator.
Heroes is similar to the "Tron" and "Nibbles" games of yore, but includes many graphical improvements and new game features including 12 original soundtracks, 94 levels (in 10 different tilesets), and five gaming modes including Quest (the classical Nibbles), or Kill'em all (squish the lemmings).
Sawmill is a log analysis tool which can be used to analyze Web site traffic, proxy usage, ftp usage, and much more. Major features include a persistent database for long-term tracking of statistics, hierarchical data mining features, and many security features appropriate for use in a multi-user environment.
rsyncbackup is a handy tool for scheduled backups using rsync. rsyncbackup lets you easily setup multiple source folders and destinations, both locally, on your iPod or external firewire disk, or at a remote destination using ssh. rsyncbackup has no GUI, but is based on editing configuration files. The script is meant to be run in a crontab, so user interaction is not neccesary. Basic terminal skills are required to use the program.