I reject these sub-notebooks. They are trying to be two things at once. Either be a PDA or a laptop, you can't have it both ways.
IMO, if you can't have a full-size keyboard and full size monitor, there really isn't any point, so you might as well be using a PDA.
Like this:
http://www.oqo.com/
They actually expect people to use that "keyboard"?
Now if those little boxes are just the meat of the machine and you intend to attach a monitor and an external keyboard, fine. It's like a portable G4 Cube. I can't argue with smaller infrastructure, but in and of themsleves, they just don't look "usable".
I can accept that there might be a niche audience of tech people who are always on the road providing network support or something where they need a full implementation of an OS on the smallest, most durable device, but that's a small audience.
Actually, I just thought oa another user. Doctors making the rounds, getting full access to patient data. Alright, so maybe it's not quite as stupid as I think, but I still think it's very niche. For general users, students, designers, editors, programmers, office workers, etc. I just don't see those things taking off.