I hate the fact that I don't have business cards; it makes it so tedious to exchange contact information with colleagues at conferences. Networking should not be hard! In many departments, graduate students typically do not get business cards, but I got around this by ordering free ones from Vistaprint. I only had to pay shipping, and now I have hundreds of cards! Enough to last through more conferences than I even want to think about, and certainly enough to make it to graduation and a real academic job, where I will get real business cards! There are plenty of designs to choose from; I chose one that looks fairly official and staid, but that's just me. Go get some cards!
P.S. Vistaprint has several other free offers, and they regularly post deals and discounts on lots of other products, so it's a good site to keep an eye on!