Just found this on my friend's Xanga blog:
If you have an American Express card, just use it 2 to 3 times at certain store or restaurant between 4/1/08 and 5/31/08 and you can mail the redemption form to American Express to get 4 free movie tickets. I think the best deal is to buy three regular tacos at Del Taco since it's the cheapest. The claim form for Del Taco is here.
Actually, you can get 4 free tickets to a museum too, but the website doesn't say what museum is participating... :P