Years ago I had a 47 Chevy pickup, and I installed a pretty chrome push button where the radio would be if it had one. I had it hooked up to a electric oooogah horn that was mounted under the passenger side of the seat.
It was surprising the number of people that would just reach up and push that button without asking what it was for..... And the ones that asked, I would tell them I don't know what it is for, I never pushed it.....