DIFFRACTION LENSES! They're the best party trick/people meeting tool ever! "Hey! Hey you! Wanna see something cool?" I carry a pair with me at all times, no joke. I got them from a random dude at Burning Man -- probably don't need to explain how much more awesome they are in the presence of a desert-full of blinky lights and already skewed perception.

I'm bummed that I lost that XXXenophile card you gave me in a wallet theft. :(