What makes a good business card?

I'm working on a feature for the next issue of UPPERCASE magazine. I'd love to hear your opinion:

What makes a good business card design?

Please leave your comments below this post with your name and url.

Are you proud of your own card or one that you've designed for a client? Submit print-resolution files here by November 15 to be considered for publication in the magazine. Make sure to include your contact info and all appropriate design credits.