Here's Brian Brushwood showing how to do a great mentalism trick. The effect: Brian explains to the spectator that a psychologist once taught him about a famous Robert Frost poem that, when recited, will force the person who hears it to imagine a specific playing card. Brian then recites the poem to the spectator and asks the spectator what card he thought of. Then Brian tells the spectator to do a YouTube search on the psychologist who told Brian about it. The spectator plays the video and the psychologist says the same card the spectator thought of.
Brian Brushwood's mind control magic trick