If you want to see a technical look at what the "think tankers" are doing with physical world hyperlinks, Nearfield has a great summary
The proceedings are now online (pdf)
A couple excerpts.
This project explored user-reactions to two different kinds of physical world interactions: barcodes and RFIDs. It tested what they thought of each technology, and how they might interact with them.
This project prototyped two interactions with consumer products where the mobile phone replaced some of the physical interfaces that otherwise would have been part of the product themselves.