Dijjer is YAP2PC (yet another P2P cache).
This is cool, a publisher doesn’t even need to do anything to support it.
My suggestion is to use an HTTP proxy instead of a regular webserver. This way, all web data would work with Dijjer, not just stuff explictly used.
Ultamitely, though, this is only a transitional solution. Eventually, we will all want to move to hash based content distribution systems. As for metadata, again, we’ll use the XML-based IM standard, XMPP.