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).
The modular syslog allows for an easy implementation of input and output modules. The modules that mantain compatibility with its precursor are included in the standard distribution along with four modules: om_peo (an implementation of PEO-1 and L-PEO, two algorithmic protocols for integrity checking), om_mysql and om_pgsql (modules that sends output to a mysql and postgresql database, respectively) and om_regex (a module that allows output redirection using regular expressions).
PLIB is a set of libraries to write games and other realtime interactive applications that are 100% portable across a wide range of hardware and operating systems. It's used by Majik3D, FlightGear, and others, and includes libraries for GUI widgets, sound replay, geometry, scene graph, joystick, and fonts/text.