You could probably find a laptop like I have, an Averatec 3270, for fairly cheap. If 2 to 3 hours of battery life is ok, this is a nice little laptop. 12", so it's rather small, it does great for typing. The video card sucks, but it'll play videos just fine, just no gamming. The processor is plenty fast just for normal stuff, I normally underclock mine to 800MHz to save battery and it's really not even noticeable. It has a DVDRW in it too, which is really nice for this price range, and a 60 to 80G harddrive, which is also great for the price.
Newegg had one for $700 I beleive, but there are probably cheaper ones around as this particular model was recently replaced with a slightly newer model(Sempron 3000 rather than 2800, new case)