At last month's Firefox Summit, everybody got a nice name tag on a lanyard to carry around their neck. That was extremely useful, especially since people frequently put their real name as well as their IRC nick on there.
This is how it looked like (involuntary model: Mike Shaver):
After the summit, though, the name tags and lanyards went into everybody's bottom drawer. Well, everybody's but mine :)
I removed the name tag from the lanyard and connected a key ring to it, turning it into the coolest keychain ever: