I saw somewhere in a demo, a magician put a pen in his fist and do slot machine gesture then produce lots of coin.

I believe it's one of the routine in the demo, and not sure if its a demo of a gimmick or just dvd.
It is relatively new product.

Does anybody know what I am talking about?
Please tell me where I can find it.

thank you

Look in Richard Kaufman's The Complete Works of Derek Dingle, Slot Machine, p. 100.

No gaffs.

Thank you!!

My pleasure.