interactive visualization and exploration platform for all kinds of networks and complex systems, dynamic and hierarchical graphs. Runs on Windows, Linux and Mac OS X. Gephi is open-source and free.
software version control visualization tool
cdcover analyses MP3s and other audio files, generating a picture of the waveform for each track, suitable as "album art" for an ID3 tag, or for combining as a single "CD cover"
sequence diagrams of several protocols in PDF