Okay, so let's say that Piaget, Vygostky, Papert, and others were right, and that knowledge is constructed by our experiences from the world and one another.
And, let's say that apart from being a powerful delivery system for gossip and pornography, that the Internet allows, facilitates, and develops these types of learning interactions.
You should look at the new tool from the Smithsonian, Smithsonian Commons, which lets all of this happen powerfully.
(Thanks to the folks at O'Reilly Radar for this!)