> Having the exact same computer following us around without transmitting everything to Big Brother would have a certain amount of appeal if not for the greater danger of losing everything with our phone! So, what's next?

Ever heard of Citrix, VDI etc.... that is exactly the concept you are explaining and its available now. I can hook the citrix receiver on my blackberry up to my citrix desktop then plug in the microHDMI cable and attach a bluetooth mouse/kb. Sorted, full screen enterprise class desktop applications in a secure container.

This isn't some revelation, it's achievable today