What laptop for gaming

I'm going traveling in a couple of months, and have just relalised this is going to leave me out of playing computer games, like UFO Aftershock (comming out about a week before I leave!) so it got me thinking, if I could get a cool laptop that can handle these games, should the need arise were surfing/sightseeing/drinking doesn't appeal I can turn to a trusty gaming machine. Now where better to learn about the best laptops on the current market then here! So here goes

My requirements
Long battery life - my flight is 24 hours, I'm not in 1st class so no recharge option!
Cheap extra battery costs - same reason as above.
Small - I'm travling so weight and pack space is limited.
Cost - upto 1500GBP (I can get from america before I go if I can get better spec for the money)
I want to play games like UFO/Command & Conquer/Simcity etc
I would like to use it to watch DVD's

any ideas welcome!