I'm about to get a MacBook Air and I was thinking about its lack of serious performance and lack of a docking station. It occurred to me that the main thing i want from a docking station over just moving to a desktop when i need more cycles is preserving my "session," i.e. the set of open programs I have.
People have tried to do session migration before, most notably I think in clustering systems for migrating distributed processes, though in some sense screen and even the original VNC allow you to move sessions across terminals.
What I'm proposing is to take advantage of modern suspend features of laptops to migrate a session. The model is this: Suspend the laptop to disk, connect it (perhaps via a firewire target disk mode-like mode or its moral equivalent over ethernet) to another computer and have that computer resume the laptop in a virtual machine. Desktop software is already robust to suspend/resume and the potential change in devices or network connectivity.
It seems like it would be pretty possible to do this in Linux but not really possible to do it for Mac OS X, which is my main platform these days.