decentralized web(site|log) update notifications and content distribution / September 9, 2004 8:25pm @ trainedmonkey:
maybe it's useful to sketch out a scenario of how i envision this working: i decide to track a site like boing boing, so i subscribe to it using my aggregation client. when it subscribes, it gets a public key (probably something i fetch from their server, perhaps embedded in the rss/atom feed). my client then hooks into the notification-and-content-distribution-network-in-the-sky, and says "hey, give me updates about boingboing". later, the fine folks at boing boing (or xeni) post something, and because they're using fancy new software that supports this mythical decentralized distribution system, it pushes the entry into the cloud. the update circulates through the cloud, reaching me in a nice ln(n) sort of way. my client then checks that the signature actually matches the public key i got earlier, and goes ahead and displays the content to me, fresh from the oven.
This is pretty much what mod-pubsub (and many others) can do right now via HTTP. There is a SourceForge project that has clients in several languages (I did one of the Java clients - there's a Snoop console app that's fun to use to peer into the stream) and two server implementations (one in Perl and one in Python).