If you’re a Blockbuster customer you may have received a postcard offering “Unlimited Free Rentals” though July 4th. Well, here’s the catch. You get a free 1-day rental whenever you rent a new release for $2.99. The free movie must be a $1.99 rental or less, and you can only have one out at a time. The promotion doesn’t include games (or, oddly enough defensive driving courses). New movies include such titles as Black Swan, Diary of a Wimpy Kid, Harry Potter and the Deathly Hallows Part. 1, and Kung Fu Panda.