MobileIP (Score 1)

Actually it is funny that this topic has just surfaced, Im in the process of finishing a thesis studying Mobile IP actually MIPv6 and its capabilities, you'd be extremely surprised what you get when you start putting a few things together, using 802.1x and IPsec we can ultimately reduce handoffs between access routers on the same prefix to ~50ms or less and thats with an 802.1x authentication!! Sutff like this is really possible and can be done today without major infrastructure changes, we just need to start doing things. I think in the next few years we're going to see the next Major leap with technologies like this and the upcomming "Cell" processor (I cant wait for this one).

BTW if anyone is interested do a google for MIPv6 you can narrow it to the ietf.org if you want. Killer stuff.