There are some great bill change routines/methods and Slow Burn is my favorite. I think it looks like trick photgraphy. You'll fool yourself in the mirror with it. This is what you ( and laypeople ) expect real magic to look like. A "wave" of the hand and the change happens. The displays before and after are so clean.

You can see a clip ( if you haven't see this, you'll order it when you pick your jaw up off the floor ):
http://www.sandersfx.com/slowburn.html