I have been thinking about an entirely cloud based computer for a very long time, instead of a decked out computer, you would have a subscription and a minimal set of hardware, the only real limitation is internet speeds, or connectivity. if you can get ping under 10ms and then have huge servers to process information faster than any personal can affordably hope to do it would make sense to "rent out" computer storage, speed and processing power.
The consumer has only the screen, internet connection and RAM to house instead of an entire computer. with adequate internet a laptop can now be more versatile and more powerful than a desktop for minimal cost difference.
I feel like Drop-box is making the first steps towards this kind of virtual computing (somewhat ironic) platform, and i am going to be watching very closely.
I always thought google would be the first to do this, is suspected it was one of their reasons for starting google fiber, to provide sufficient bandwidth to an average user to make true cloud computing viable.