There's a nice one, I think its in volume 4, called the "knowledgeable cards" or somesuch thing. In any case, its a solution to the Hofzinser 4 ace problem and I used it when working for a short while before I got started, always got a good reaction. The only reason I stopped using it was because I found a far better trick based around the 4 ace problem in Jack Parker's "52 memories".