Developed it ourselves, well the JavaScript terminal is shellinabox (http://code.google.com/p/shellinabox/) but it's connecting via websockets to a Tornado server that does all the interesting stuff.
Incredible! I really wish this was at my disposal when I started working on my side project a couple months ago.
I haven't even played with PythonAnywhere yet, I'm just commenting on how great the tutorial is. It excellently fills in the gaps between django and the facebook interface.