"A particularly useful class of URI schemes are "Self-Verifiable URIs". These are URIs with which the URI itself can be used to verify that the content has been received intact. We also want URIs that are content-specific and can be independently generated by any host with the content. Finally, to show the intent that these addresses are location-independent, a URN scheme will be used.
Cryptographic hashes of the content provide the capabilities that we are looking for. For example we can take the SHA-1 hash of a piece of content and then encode it using Base32 to provide the following URN. urn:sha1:RMUVHIRSGUU3VU7FJWRAKW3YWG2S2RFB" This is awesome. I explained this concept to Jeremy about 6 months ago. Its whats needed to allow MemeStreams to be used to access and recommend p2p content. Glad I don't have to do it myself. :) Only issue is that they are looking for browser implementation. They can't rely on browsers. They need to build a driver that sits on top of your ethernet driver, looks for these urns, and modifies the access method appropriately... HTTP Extensions for a Content-Addressable Web | 
