Magic Tricks

Clever gimmick, allowing for an easy peek of secret information.
If the manufacturing is not really difficult, it will require a couple of trials to get everything perfect (thickness of construction paper will have to be factored in to get a perfect result). It remains more complex to build than other w** envelopes and will not be built on the spur of the moment (hence the loss of a star in the rating).
Handling wise, the move is a little bit angle-sensitive (think Acidus Novus). In a one-on-one situation, the effect is outstanding.
All in all, a great addition to the arsenal of the mentalist who likes to use envelopes and billets. Perfect for a single Q&A reading, medium-style.