Have you seen my Moo cards? They're half the size of business cards, and you can pick a selection of photos that get printed on the backs. I hand them out when people ask how they can get a photo I've just taken, or when I meet fun people in general. People always love them; they're completely different than handing out business cards. I've got some hockey photos, some scenery photos, some Grassroots photos, and so on.
Just ordered a fresh batch, and Moo gave me a link you can use to get 10% off your first order -- and if you do, I get a discount on my next one.