TinyScheme is an implementation of the algorithmic language Scheme that aims to very small memory footprint while being as close to R5RS as practically feasible. TinyScheme is also a good base for hacking, given the implementation's small size, easy gluing with C and code being fully reentrant.

Rlpr makes it possible (or at the very least, easier), to print files on remote sites to your local printer, and vice versa. The rlpr package includes BSD-compatible replacements for 'lpr', 'lpq', and 'lprm', whose functionality is a superset of their BSD counterparts. In other words, with the rlpr package, you can do everything you can do with the BSD printing commands, and more. The programs contained within the rlpr package are all GPL'd, and are more lightweight, cleaner and more secure than their BSD counterparts.

This munin plugin uses the Python btrfs module to retrieve information about disk space allocation and usage.

Sliding block puzzle game, similar to Klotski.

Quick Spam Filter (QSF) is an Open Source email classification filter, designed to be small, fast, and accurate, which works to classify incoming email as either spam or non-spam.