Who said netbooks were only good for browsing the web?...
The QuakeLive beta runs happily in a netbook's web browser
The unusual thing about netbooks is that unlike almost any other piece of technology created, those involved in their manufacture and marketing try their best to downplay their abilities. The reason is vested interest: if folks start using their netbooks as gaming or media machines, it could significantly hurt sales of full fat laptops.
It's quite astounding how many games will run on the current generation of 1.6GHz Atom netbooks, though. You don't need a supercharged PC to make games look good on their low res screens.