Dave Winer needs spicy noodles. So, he finds it by searching his blog via Google. I think people use blogs increasingly both to remind of discrete facts, as well as of more complex (if abortive) ideas. Microsoft, among others, is trying to come up with personal diary/databases (they call theirs MyLifeBits) that would give you the ability to extend your memory in just this way.
Blogs of various stripes, outliners, personal datamining, and the semantic web generally–all of these are beginning to look like the next revolution in networked computing: a revolution of the social mind.