Alot of new and old Linux games are appearing on Steam and SteamOS some of them are very CPU friendly aswell and can easily be ran on quadcore with basic laptop videocards.
If you use an external drive say around 2TB you have yourself a pretty nice portable gaming rig aslong as you can install the steam client.
usually you can get deals on these games so watch for them.
left 4 dead 2
serious sam 3
Valve Complete Pack
or maybe just orange box-
-halflife2 – counterstrike – dayofdefeat.
star wars knights of the old republic – the sith lords
descent 1 2 3
the curse of monkey island – you just have to use your own scummvm install to run it with “scummvm -c monkey3.ini” in the steam directory
company of heroes 2
world of goo
ibomber defense pacific
condition zero deleted scenes — great single player mode if you like counterstrike.
LIT : bend the light – you have to turn the resolution down and enable vsync to make it more playable same with most of the other games. i like 1080×720 resolution
a few others and some in the wishlist still there are lots