Here's something to try that will get your cow-orkers looking strangely at you:

Trick
This is kind of dumb, but fun. While sitting in your chair, lift your right foot slightly off the ground and move it in clockwise circles. Now draw the numeral “6” in the air with your right hand. Your foot will involuntarily reverse direction. (via hanging-fire.net) [via Making Light] [via Boing Boing]

Note, It doesn't seem to work for all people. I'm sure there's some explanation for all of it.