If your potatoes are already sprouting on you or going bad, don't throw them away. Nick Engler has a way with potatoes to help get rid of rust on metal surfaces. Be prepared though. Anything left to rot in water is bound to stink!
OK, if that is not your cup of tea, try using your potatoes to propagate wood stem cuttings.
Learn how to do it right from Back Yard Diva. You can't fail growing something with this method. If the cuttings failed to take root, most likely the potatoes will.