What's one of the ways you goof around with your friends?

I got a new one were if I see a buddy walking around town - I'll stop and talk with them a bit. Then I will point to a parked cars licence plate and say if you turn that licence plate upside down it spells boobies. Guys always what to see boobies so they will look at the plate - turn their head to the side and try to see some boobies.
Cheers and happy weekend!