I do a bit known as the "Telepathy Challenge" I picked up a few years ago from Stephan Magus in the U.K. (Magus Magic)... from what I understand Max has a similar piece out as well e.g. on the day you sign the deal for a gig, you ask the event coordinator to help with an experiment.
The VIP in question is given a drawing pad, some colored pens, etc. and asked to draw any design he/she would like using the pens, and so forth to do so. They are then told to fold the drawing into a small packet, seal it into an envelope, etc. and keep it with them (making certain they bring it) the night of the show. NO ONE IS IN THE ROOM AS THE DRAWING IS MADE. NO IMPRESSION SYSTEM, ETC. EVERYTHING IS ON THE UP AND UP... (sort of).
Needless to say you comment about this Telepathic Challenge made by the event's organizer, go through all those convincer questions that prove you didn't cheat or you're not in collusion, etc. only to draw the same exact drawing using he same colors... getting an overwhelming round of applause (well, that's usually the case...)
It's dirt simple and works well!
I've also used Banachek's Psychological approach in which the spectator visualizes his/her front yard or what it looks like outside their business office, etc. (see Psychological Subtlties)