QR codes are very cool as they link electronic media with real-media.

http://reader.kaywa.com/

Wouldn't it be great if the LIFT09 conferences badges had QR codes!

Here are a few links:

http://www.microlearning.org/micropres07/ml2006_presentation_kaywa.pdf
http://www.youtube.com/watch?v=9DlxCpvAx84
http://www.kaywa.com/rss2/