http://phillynewmediahub.com/ has a bunch of stuff, though not these hackathons. http://macalliance.basecampbusiness.com/calendar/search has some stuff too, though more bizy than hackathony. Also missing though is Philly Lambda (http://groups.google.com/group/philly-lambda), which has hacker speaker type events, and PSL (http://phillystartupleaders.org/), which has startup focused events.