The exchangable cookie (we called it tokens/knapsack) idea was discused
many hypertext design sessions held by the davenport group. Everyone was
excited about the possiblities. Cookie semantics ranged from "have you
seen document x" to "do you prefer video" were discussed. Indeed, it seems
that this is the start of a client/server agent information exchange
protocol.
As always, I am looking for more...but I would be delighted with
session ids alone.
Dave Hollander