I had two of the three fans on my old HP laptop go out, and we didn't really want to replace the fans, as a new laptop was in my near future at the time. We bought a
Targus cooling mat and it worked beautifully.
I have a lapdesk that I use, so my laptop is always on a smooth, solid surface. The cooling mat, which was about half an inch thick, sat underneath my laptop. It kept my laptop cool, and I was able to use it for several months longer than I thought I would... My laptop was getting so hot that it would turn itself off, before I got the cooling mat. I got my new laptop for c'mas, but I'm keeping the mat, just in case.