Everyone knows "Punch Buggy" and/or "Cruiser Bruiser". This is the same. When you see a Scion xB (the one that looks like a toaster with wheels) scream "Scion Slap" and slap the crap out of someone in the car with you. Same rules a Punch Buggy only difference is slapping and not hitting. Its fun and almost always starts a brawl in the car.
While in you car you see a passing a Scion xB.
You scream: SCION SLAP!!!!!! (slap someone)