I've been dreaming of true computer switching portability for a long while. What I mean is that my primary work machine, my travel machine and portable machine are all identical and store the same state whenever i switch from using one to another, except with varying levels of computational power (hardware). Imagine working at home on a powerful machine and you feel like going out to work. Take your portable machine to the coffee shop and everything is there like your powerful home machine, except with lower hardware specs.
It is hard to imagine working without local files on your computer and Chrome OS still needs to work out how to handle interfacing with other hardware (hard drives etc) but this seems like a step in the right direction.