Put 'Em On the Glass

Putting their money where their mouth is, a few years ago, 3M stacked what seemed to be a few million dollars in cash between two sheets of their proprietary security glass mounted on a bus station. They gave passers-by the opportunity to kick the glass, and even with a running start, none were successful. In reality, the money was fake except for the bills on top which amounts to roughly $500. Excellent, thoughtful promotion nonetheless.