I'm going to SpaceUp DC tomorrow and Saturday! It's an "unconference" for space enthusiasts, being held at GWU downtown. An unconference is like a conference, except there's no division between presenters and attendees -- anyone can do a presentation, and all the activities are encouraged to be interactive and dynamic, rather than one-way. Part of the reason it grabbed me was this video, and its point about how the most interesting part of most conferences are the hallway conversations in between sessions, not the sessions themselves.
I always think I'm going to enjoy sessions at conferences and conventions, but I often find myself getting bored and fidgety, or ducking out halfway through if I've remembered to sit near a door, so this really rang true with me. Hopefully this format solves the problem. We'll see!
Anyway, if you're into this stuff, consider coming down! It's local, it's cheap, and it should be fun! But you do have to register in advance at the website; they aren't selling tickets at the door.