Just forgot to add to the list Dangerous Waters where I just until now scratched the surface and which will also surely keep me busy for a while, and I just remember I have at least 50 skirmish maps I didn't try yet in W40K Dawn of War...
By the way my son just bought a laptop with AMD Core Duo, 2 Gb DDR and 256 M Nvidia video card and I could bet it can run most of the games.
Once again I don't pretend it's the best, but just to say it is quite possible. When you have a life where you are a lot on the road (like me...) it can make sense. When I come home, I just plug in my TFT screen and external keyboard/mouse.