The 'Air steering wheel'

I among many others are guilty of pretending to play air guitar,air piano when a great song come on.
I was just sitting at traffic lightly tapping my fingers in a ladylike kinda way on the steering wheel to the Scissor Sisters when i look across to another cara nd the guy is beating the hell out of his steering wheel, ok a good song must be on with plenty of drums ...but then he usd it to play air guitar!!!

Curious I thought, can the steering wheel be classed as an instrument and what instruments are you guilty of turning it into??