Here’s a great video showing that even advertisers themselves are susceptible to unrecognized influence (assuming it’s genuine as Derren Brown is an illusionist and his television performances often involve trickery). Be sure to watch right to the end:
(linkage: http://www.youtube.com/watch?v=ZyQjr1YL0zg, by way of Terry O’Reilly’s blog Age of Persuasion)