My beloved 3years old Macbook Pro was starting to get really hot when I used it. It had gotten to the point where I would burn my legs if it was on my lap, and since having your laptop on the lap is kinda the point, I felt had to do something about it.
I bought a Logitech Notebook Cooling Pad that actually is very comfortable and does exactly as it says it will, but I was still curious to see if I could get my old healthy Macbook back.
I found this blog post about how to vacuum the laptop and the result is amazing. I was a little worried about the static, so I turned the machine completely off and removed the battery before vacuuming. The happy laptop is now quieter and cooler! Very simple and very recommended.
Image from noor*.