Idle Thumbs are hosting a game jam, Wizard Jam. It's running from April 10-24. Looks like there's lots of help available with a whole bunch of game engines, programming languages and tools (including GameMaker, which I've been using).
Have to say, I was tempted to sign up, but then I remembered what a procrastinator I am. Me and deadlines, we... well, we don't really get on. Still, for anyone who doesn't mind deadlines or who would like some help or advice, it seems like a pretty good opportunity.