my mom actually had frequent, really bad foot and leg cramps, and then she stopped drinking coffee and they went away completely. i guess the caffeine did something. i'd highly recommend trying to stop if you drink coffee.
other things she uses to help are magnesium supplements and tonic water (quinine should help)
also, stretching, i can't stress it enough. super important and very helpful if you do it frequently, before and after skiing especially.
i'm no doctor, but good luck man. hope they go away.