When you are using the laptop do you have it sitting on your legs. Maybe you should try getting a laptop "board". My laptop recently died and i am pretty sure it was because my wife never let it get proper air flow, due to it sitting on her legs.
Anyway. I would say try to get a flat surface. There are laptop "stands" that are mesh metal on the top to allow maximum air flow. Newegg had a nice one a while back.
HoFL