I just found out about this today: http://www.nationalpinballmuseum.org/
Anyone in the DC area up for taking a trip over there? It's in Georgetown near Wisconsin and M St (specifically, 3222 M St NW), so not super metro accessible, although there are buses that will drop you off near there. Also, it's only open Thursday - Sunday. It's $13.50 most days, but on Thursday, you can pay $20 and get unlimited play on their machines.
What do you all think is the best deal? If people wanted to go on a Thursday night after work (although it's only open until 8 pm), that'd work for me just about any week. But if we want to go on a weekend, I'm free this weekend, and then not again until the first weekend in June.