You're asking for portability and gaming capabilities ... Two things that you can't find in most ultraportable laptops...

You have the Dell XPS M1210 that can be "acceptable" for playing games. Sure, it has a GeForce Go 7400, but with only 64 MB of on-board VRAM, the rest of the 192 MB is shared with the system RAM, and loosing 192 MB of RAM slow down the system...

Comes after Sony : http://www.sonystyle.com/is-bin/20INTERSHOP.enfinity/eCS/Store/en/-/USD/SY_DisplayProductInformation-Start?CategoryName=cpu_VAIONotebookComputers_SZSeries&ProductSKU=VGNSZ320P%2fB&TabName=specs&var2=

I like this model because it has a very nice graphics system. You can boot on both nVIDIA GeForce Go 7400 ( 128 MB on-board I think ) and the Intel 950. You'll use the nVIDIA graphics solution to play your games, then you'll swith to the Intel integrated IGP to save power form battery. The only bad point : it is very expensive. Over 2000 $ with taxes ...

You'll get poor graphics performances with the integrated nVIDIA 6150 of the HP dv200z. Also, the Turion X2 isn't the best processor and the Core 2 Duo or even the Core Duo delivers better performances.

I have a Dell Inspiron E1505 with an ATi Mobility Radeon X1400. I can get pretty good gaming performances, but it is a 15.4", which is not the best for a student...

There is also ASUS that make very nice laptop. But on the American territory, ASUS is not a popular brand ( except for their desktop motherboards ) and the after-sale service might not be the best ( it is not a popular brand so ... ). You can find nice models form ASUS with good graphics solution.

Good luck !