If you've been living under a rock, Minecraft is a hit "new" computer game made by Notch. A few months back, they came out with codes that were an alternative to using a credit card. I checked, and can't find them in the email/mail section, or Gallery. I think it would be a good idea to add them.
Sorry if this is a re-post or its all ready on the site, I'm new to the forums.