This is why I go the desktop/netbook route. Cheaper overall, and the laptop is basically disposable. If you break it or lose it, oh well. Not the case with the Macbook.
All my code is on version control, mail and calendar are "on the cloud" and all important files are rsync'ed to another machine that would be perfectly happy with a serial terminal (but has hardware accelerated graphics because it was cheaper this way).
On my desk you will find a mouse, a monitor and a notebook stand. No need for more, really.
Actually, we have that degree of CPU power on the phones already, for a value of "full-blown PC" from years ago. What we need is more support for the use pattern in the OS/software.
Take your data everywhere and have it synced with the cloud for backup/web access in a pinch.
EDIT: Software does this, if you are savvy. I'm talking about becoming the mainstream use pattern.