I use a Dell Latitude D600 and its been great when I actually use it...
The 2nd internal high capacity battery is a must, I get about 6 hours of recording time with it.
Windows 2000, min. 512 RAM, etc...
Used it with an unmodded UA-5 for a bit...its pretty small, and light, durable (I've beat it up pretty well).
This is a 2yr old model though.