I kind of want the opposite. I've got a big, capable laptop at home, and several computers at work. When I go out, though, I'm not going to do any real programming or make a presentation or things like that when I'm at a cafe with my wife, or sitting on the train home from work. I'll surf the web, read a paper or play games. A tablet lets me do that just fine.
A small, light laptop has too many compromises; little memory, slow CPU (that gets throttled after more than a few seconds at 100%), small screen and keyboard. And it's still much heavier than the Tablet Z I carry. The tablet is light and thin enough that I really don't notice it in my bag at all.
We're all hunting for the impossible: a matchbox-size computer with the power of a workstation and a 40" screen. Instead we have to compromise. And we all end up with different compromises. I've even thought of cancelling my smartphone and go back to a small, light feature-phone. It's cheaper, more durable and the battery lasts for a week. Use only the tablet for apps.