Wax

It's uses are too numerous to list, but every magician knows that at one time or another magician's wax has played an important role in the outcome of one of his effects. It's a utility item that is probably found in every magi's bag of tricks. Use it with cards, coins, thimbles, cigarettes, etc. Great for making an impromptu paddle effect at the dinner table, and so much more. If you have it, you'll use it!