I just wondered if there was a back-story .. how you might use them. /. has a recent post on the "death of the business card", mentioning that personal QR codes are getting used for "social networking:
http://goo.gl/UEmTM
All: are any of us using them? If so how? If not, are you thinking about it?
Apparently people want them on their business cards too, so they can scan them once home. Bump is apparently pretty widely used, 77 million!
http://bu.mp/ but I'm not sure if I want them to have my info.