I know what you're thinking: "Redbox is already as cheap as it gets. There's no way that you can secure a movie rental for less than $1.20. Besides, how pathetic are you?"
Answers: Free, and very.
I feel bad about using the movie kiosks to begin with; I know that it feeds a system that supports big budget releases and makes distribution for smaller films more difficult while simultaneously applying fiscal pressure to the few remaining mom and pop video rental stores.
That said, I use the thing. All. The. Time. It's a proximity/convenience/cheapskate kinda issue. Also some of them have those cheesy sci-fi movies that I love so much, like MegaPiranha vs Sharktopus.
Last night my world changed when the guy standing in front of me gave a promo code to everyone in line. I asked him if he was doing a guerrilla marketing campaign for the company; he wasn't. He subscribes to a site that gives out lists of active codes for free rentals. (Late fee charges still apply, so return it.)
Here are a few that currently work: DVDONME DVDATWAG (Walgreen's exclusively) BREAKROOM
You will still have to swipe your credit card, but the amount charged is zero. Each code is good for one rental, but the codes will eventually expire. Here's a link to the site so that you can check in on new codes and feel like you beat the system.