A few days ago I read on Meredith Barnes' blog about QR codes, which are images that smart phones can scan to go directly to a website (they can also encode other data, like phone numbers). They're showing up everywhere (or, now that I actually know what they are, I'm noticing them more). While I don't have a smart phone* but lots and lots of people do, and QR codes are ridiculously easy to make using the link in her post, so my next set of business cards will have one on the back. Or you could put them on fliers for your groups, sports teams, recipes, anywhere a link could go. Pretty dang cool.
(*not out of any rejection of technology or anything like that, I just love my flip-phone)