Well, a clear indicator that QR Codes have made it ... they appear as a key clue in a recent CSI programme :-)
See the video (2 minutes on youtube) - http://uk.youtube.com/watch?v=P-DntIQi2e8
Thanks to Nitin for the heads-up with this one, and the original blog post on http://2d-code.co.uk/qr-code-clue/