Don't know if someone's mentioned this already, but have you looked at the hawkeye knobs? They replace the standard knobs on your pedals, and can get bumped without changing settings. you have to lift them up to rotate:
alternatively, you can look at: loknob.com
Althought the loknobs have to be stuck to the pedal.
WELL shagING GREAT NOW I NEED TO BUY ATHOUSAND OF THESE. THANKS A LOT.