battery life on gaming laptops suck, trust me. I had a Dell XPS Gen 2 and I couldn't play games without having it plugged in. Plus, I'm pretty sure it gave me 3rd degree burn on my lap too...
There's an Asus machine that's fairly small and it has a GO 6600 which seems like a fairly decent video card for a laptop. Sure, it won't be able to play FEAR and UT2007 but should play that Dark Ages of Camolet game.
Check notebookforums.com in the For Sale/Trade forum.