We've got another Hackathon going down in January. My coworkers and I will be there playing around, helping out, and raising hell. We're bringing a Raspberry Pi, a few Arduinos, and quite possibly a dirigible to this event. If you want more information, or to register or show up, visit mhacks.org.
The site does a poor job of advertising that it is for ALL people, not just college and high school students. If you're a geek, nerd, or just like electronics and want to show up, and spend 36 hours hacking away at some various and interesting electronics projects. I suggest you get on that site and register to attend (or if you're old like me, send them an email).
Check out some pictures from the one in September.