At this year’s BISG Annual Members Meeting Carolyn Pittis gave an excellent presentation on QR Codes [Wikipedia link] (2D barcodes that can repesent text) and how they are being used by Harper Collins to link books to mobile websites and extended content. Harper is including a QR codes on the back of some books that can be scanned by cellphones and used to link to a mobile website that has extended content for the book. QR codes can also be embedded on marketing material, posters, etc.
Why is this interesting? Think of the number of cellphones out there. Perhaps the QR code could link to a mobile site where the book could be purchased for the cell phone that scanned it, or too a site with some extended content that was made specifically for a mobile platform.
Here is a QR code for the BookNet Canada url.