Danny Sullivan mentioned above how funny it would be to have the teams in his kids games sponsored by GOOG/MSFT. This got me thinking, what if Google Adsense could move Ad inventory onto something like a football/baseball uniform(in addition to Billboards & Posters). Would you just use a QR-Code to register when a sponsored media ad unit has been hit by a phone(when taking a picture)? The people who manufacture T-Shirts and Jerseys could be given the QR pattern when they silkscreen.
When parents upload their pic's to Flickr, visible QR codes could be decoded by the site in the background or your browser, or both to figure out what to do with it. Even a partially obscured or fuzzy code could be useful if the other metadata(location, time, comments) in the photo allows a good guess as to whats going on.
Matt Cutts has posted a very cool feature from Google's URL shorener that would make implementation of this QR concept much easier.:
"Here's a new trick that hasn't been blogged yet! Google's url shortener at goo.gl can generate QR codes (which are 2D barcodes) just by appending ".qr" after the goo.gl url. So the urlhttp://goo.gl/727X does a redirect to http://www.mattcutts.com/blog/ and the url http://goo.gl/727X.qrwill generate a QR code that also goes to http://www.mattcutts.com/blog/ . Pretty cool, huh? Please share this trick widely. :)"
Matt had a really good seed for discussion in the Buzz thread later on, about making the QR with infrared, such that phones could see them and people could not.
Brainstorming The Future #1 now available for viewing. Follow the Buzz thread brainstorm for a new concept in QR-Codes.