BRL-CAD is a powerful constructive solid geometry solid modeling system that includes an interactive geometry editor, ray-tracing support for rendering and geometric analysis, path-tracing for realistic image synthesis, network distributed framebuffer support, and image and signal-processing tools.
MP3DB2 is a collection of bash scripts for keeping track of large MP3 collections. It will retrieve song information from the filenames and ID3 tags of a directory or CD of MP3s and store them in a local database. It then allows you to search any of the fields, generate a master listing of all your complete albums, see the size of your entire collection, and more.
OBLISK (Open Binary Linux Install System Kit) aims to make any package install on any modern GNU/Linux system. OBLISK packages are sent in an appdir-like package and can be run entirely in place, but also have an installer, which makes it possible for them to be installed to /usr or any other path.