If that's all you're gonna use it for, have you considered one of the new tiny ones? This one will only be $299: [link]

Or maybe the Asus? [link]

Hmm. My only concern with one that small would be whether it would have a comfortable keyboard, because this will be my main computer.

The tiny ones all have USB ports you can attach a keyboard of your choice to. The one thing that would worry me about those is spending a lot of time with that tiny screen. You can plug in a full size screen at home. But if you will be doing a lot of composing on the road, I'd worry about serious lost productivity.

But as long as most of your heavy use is as home (and work where they can damn well supply you with a screen), and your use on the road is light use, then go with the tiny ones. Way I intend to go if my current computer dies (though I hope it doesn't, old but suits my needs).

I know I'm predictable on this, but I'd say look at a MacBook. Even if you just install windows on it. They have a great screen, tend to last a very long time, and the magsafe powerplug is one of the best things ever.

the magsafe powerplug is one of the best things ever.

This is true....

I <3 magsafe.

Well, I wouldn't be using it for work at work. I'm thinking of taking it along so I can more easily work on my WIP during my lunch hour.

Are there relatively lightweight options that aren't the tiny ones? I want something self-contained, you know? I feel like attaching it to a different keyboard and screen would be kinda unwieldy for a computer I'm planning to haul back and forth between the living room couch, my bed, and maybe the deck on nice days.

Macbook Air is one of the super lightweight ones. I know Lenovo also makes the X300 system which is quite lightweight. I believe both are on the order of 4 lbs. and they have full size keyboards.

Well, I wouldn't be using it for work at work. I'm thinking of taking it along so I can more easily work on my WIP during my lunch hour.

For that, the tiny ones really are perfect -- they're about the size of a trade paperback, and you can easily toss one in your bag for lunchtime without the extra weight and hassle. I'll also note that the keyboard isn't an issue at all for a number of ultra-portable users I know, and is for others; no way to know until you feel it out. The screen is more of an issue than the keyboard, I think.

On the other hand, your weekend use pattern suggests something in the 12-13" range -- I'm as biased as ND, of course, but I'd also suggest looking at a MacBook if that's the size you really need. What's your tradeoff point? In other words, is portability for weekdays and traveling more or less important than having something that's all in one unit?