Really. I can imagine having one of these as my main computer (with external HD and monitor).
I probably won't and use my full-size notebook or a desktop when at home/office, but it should take me back to the days when I simply carried my Libretto everywhere because it was light enough.
Here's the best review I found so far.
People worry about the 4GB or 8GB "disk". If you keep your media (ISOs, movies, music) on an external HD, you probably can have everything else there.
Using rsync to keep two boxes synced... lots of potential.
I am probably buying two of the cheap ones.