Ctrlr controls MIDI based musical (or other) devices. There are surfaces built for specific devices to give a nice look and feel.
Edo is a cross platform utilty application. It aims to replace a lot of small tools you have to use daily, like a network enabled notepad, RSS reader, audio player, IM client, and others.
An open source Java library for DDMS.
A tool that turns messy Python imports into clean structured ones.