Symia is a minimalist C++ library for performing symbolic calculus. It is meant to be used by developers, as there is no graphical or textual user interface.
Chocoada is an Ada to lisp translator/compiler.
R.Launchpad is a minimal distribution of Linux that builds a system-image from sources into a given disk partition. It covers all the commands needed to boot the most recent version of Linux-2.6.
Database Manager designed specifically to hold XML data
A signal processing library and VST plugins package.