So as it turns out the printing company she used is called Moo and they print all kinds of business cards and greeting cards using variable data. You can basically print up to 50 different images on your cards, making each one a mini piece of art. It is a great way to show samples of your work whether it be photography, illustration, or jewelry. She also made a good point that by giving her card out and letting the person choose a design, diffuses the awkwardness of forcing your card on somebody and offers a great conversation starter.
Also if you aren't a designer or artist, but still want cool unique cards you can choose from their ready made gallery. Heck even I was tempted to order something from their gallery just because they had so many great options! Below are a few of my favorites.