Here is a new gimmick. Well I don't know if it is new or not but I just heard about it. It is called Pickpocketeer. The review says that you will be able to pickpocket 95% of anyone in your audience without having to know the art of pickpocketing. Here is a link for you.
Just scroll down until you see pickpocketeer.
The down side to these things is that the spectator still can't see the billfold. If they do the effect is ruined. One other thing I just thought about, I wonder if anyone has ever accused the pickpocket of keeping the wallet. Since they don't give it directly back to the owner and you can't exactly see the performer put it back in the spectator's pocket it does seem kind of strange. Oh well. If anyone wants to put their two cents in feel free.