The NY Times has posted an interesting article about the growing popularity of Quick Response (QR) codes in business advertising.
QR codes are barcodes with a larger storage capacity than traditional, vertical bar codes. Originally used to track automotive parts during vehicle manufacturing, QR codes are now used by businesses for a myriad of uses: commercial tracking, entertainment ticketing, and product marketing. By simply snapping a picture with a smart phone, the QR code can direct the consumer to a number of different avenues ranging from commercials and websites to games and other forms of interactive advertisement. As smartphones have grown in popularity, so have QR codes—popping up in billboards and on skyscrapers and major cities in an attempt to lure potential consumers to interact with their product.
While QR codes have many obvious marketing advantages, many people are finding other innovative uses for these Quick Response codes related to tracking and data mining. As novel uses for QR codes develop, so does its potential to help entrepreneurs devise new ways to benefit society.
http://www.jrc.or.jp/english/index.html
Example of a QR code used in advertising to help raise donations.
The QR code can even be placed on T-shirts so that you can be your own walking website.