Here's an experiment: Introduce "stock market" type pricing for movies within a fixed range, ie minimum of $6 max of $20. With a limited number of seats per theater, limited supply already exists so the more ticket purchases for a movie means higher prices. People already offer similar solutions for night clubs and bars, see http://www.thedrinkexchange.com/ as an example.

Heck, you could even bake in movie "IPOs" and make it a game. New movie ticket prices come out a week before launch and go up or down depending on the number of people buying tickets in advance.