An excellent lube is Albolene, which can be found at the drug store in some parts of the U.S. The jar, which has a blue and green label, says it's a "liquefying cleanser," but there's no soap in it. It's made for removing make-up, but it's terrific for masturbating. Apply a small amount, and you're good for an hour with no drying out – and it wipes off with a towel easily, leaving no stains. One important thing to remember about Albolene, however, is that it not to be used with condoms, since it's not water-based. Also note: Albolene seems to be sold only in certain parts of the U.S.; it may not be available on the West Coast or other parts of the world.