Dude! I'm going with an 80s theme for this totally awesome birthday card. My brothers are hitting the big 4-0 this year, and I knew they needed something fun and retro to mark the occasion. Infinity cards, aka never-ending, or endless cards, are fun to make. They are folded and glued in a way that will allow you to flip through four different designs before returning to the front of the card. They are always a big hit, especially with the men in my life who aren't really int