Back Seat Drivers

Back seat drivers can at times, can be a royal pain in the ass.
What is a person who is actually doing the driving, to do to keep his/hers sanity.
Well, you can ignore him/her.
Tell him/her to shut the hell up.
Cover his/her mouth with duct tape.
Gag him/her.
Pull over, and kick him/hers asses out and be done with it.