You guys might also like to try using my new, free app
TweetSpotter to organize spontaneous meetups among yourselves. All you need is your Twitter account.
It's a bit hard to explain what TweetSpotter does, but it basically organizes tweets by conversations (like a web forum), and conversations by location, like a virtual neighborhood bulletin board. So for example, at WWDC, you might use TweetSpotter to tweet out an invite to go somewhere for drinks to talk about [Topic X]. Other people at WWDC using TweetSpotter will be able to see your tweet and respond to your invite.
