utility for lpd printing without using /etc/printcap

rlpr

utility for lpd printing without using /etc/printcap

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.
munin plugin for monitoring btrfs filesystems

munin-plugins-btrfs

munin plugin for monitoring btrfs filesystems

This munin plugin uses the Python btrfs module to retrieve information about disk space allocation and usage.
Slide blocks to reach a goal

glotski

Slide blocks to reach a goal

Sliding block puzzle game, similar to Klotski.
an issue-tracking system

roundup

an issue-tracking system

small and fast Bayesian spam filter

qsf

small and fast Bayesian spam filter

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.
command line HDR manipulation programs (OpenGL/GLUT viewer)

pfsglview

command line HDR manipulation programs (OpenGL/GLUT viewer)

PFS is a high-dynamic range (HDR) image format. It is an attempt to integrate existing file formats by providing a simple data format that can be used to exchange data between applications.