You are bigger than advertising people. Don't let anyone tell you otherwise. Proof in the pudding? Greg Eliot of Poke has created SynchStep - a handy little application for your iPhone or iPod that matches the beat in your stride to the beat of your tunes. SynchStep is currently in private beta, but I'm sure if you shoot them an email over there, they'll set you up proper.

Go forth and create outside the box. You're in advertising. You've got creativity to spare considering your client is properly turning down all your best ones.