My husband found a Gel Mouse Pad w/Wrist Rest and nonskid base at a yard sale for $.25. I told him that if he didn't want it, I'd take it. He didn't like it.
Anyway, I wrapped my foot pedal in the shelf lining rubber-stuff from the $1 Tree Store and then put this mouse pad on top of it. I rest my heel on the gel rest and it feels so good!! The shelf lining keeps the foot pedal from moving on the carpet and the mouse pad from sliding on the foot pedal! I just put a rubber band around it to hold it in place, nothing permanent.