I agree with zmatt fully. Anything over 13.3" and above 4 pounds is just not portable for me. However, and having had several iterations of ThinkPad X series - back in '98 a 1.6kg laptop was quite something - I also don't like or recommend ULV based systems like the current X300 or the Portégé R500, because those ultra-low voltage procs just don't perform well at all, and they are stupidly expensive too. Hence, my Dell XPS1330 is by far the favourite laptop I've ever had, and I've had some very expensive stuff back when my former company used to buy me whatever I wanted.
With the XPS 1330 you can get a real proc (up to T9600), discrete graphics (mine is 8400GS, I think you can spec up to 8600M), and if you need a bigger monitor just use the built in HDMI and plug it in any old HD-Ready set with perfect image quality. There is even a free IR remote in the PC Card slot! All that at 1.8kg (cca 4lb).
As for "gaming" on a laptop, I take a different approach - I just use older games (currently on my laptop: NWN 1 + expansion packs + modules, World of Warcraft, No One Lives Forever 1 & 2). I think I'll pop on Trackmania United soon, that should run well too. It's just a matter of adjusting the mentality a bit. There are plenty of old (and not so old) games that run just fine on a system like this.
I think a low spec 1330 can be had for somewhere around your budget.
EDIT: Something a bit more on topic: Several of my staff have Acer laptops, I get good deals on them, and some have been using theirs for 3 years+ without a problem. So I guess that my experience with them is OK. I like Dell and Lenovo though. Those Lenovos are made to last, really, just like their predecessors (IBM) were. Incredibly sturdy.
