Get a free six week trial of Blockbuster by mail with coupon code: groupon. The trial period is usually two weeks so this is an awesome deal. Credit card info is required, but you can cancel the trial before it ends without being charged (I’ve already done this one, and canceling was simple).  So if you have a list of old movies you’re working on seeing, or just want to exercise your non-dependency on Netflix, now is a great time! Expires September 30, 2009. [via Groupon Seattle]