You borrow any bank note from a spectator, and give them a pen to mark it with. You then take the pen and stab it right through the middle of the note! The pen is ripped out, but leaves the note completely intact! Everything is then passed out for examination!
A classic effect that is easy to perform. Comes complete with specially gimmicked pen and instructions.
"This is a brilliant penetration, one of the best around today in my opinion, requires no switches, is fully inspectable, looks normal and blows people away!"