For months, I've been really indecisive about my logo design and thus, I haven't ordered business cards. It's a tragedy, really. I just need to make a decision and go with it, right? Anyway, I recently had the need to have something to hand out to people, even if it wasn't a full-on business card.
You can make decent calling cards in no time. I used the standard (standard American, anyway) size - 3.5 x 2 inches. You can even find a Microsoft Word template to use for this. I just added a few quick elements of importance - blog name, tagline, web address and Twitter handle.
Cutting the cards to the right size is the most difficult part of this. I used a guillotine paper trimmer, which has a built in ruler, so that made it easier. Two strips of washi tape and one paperclip later, you have a cute calling card to use in a pinch.