Mac laptops, especially the older PowerBooks, often can become very hot when doing processor intensive tasks like movie rendering, YouTube videos streaming, database lookups, or just gaming. Often just lifting the machine from the surface is enough to cool it down without the need of expensive hardware or software tuning.
Shown in the video above is one method of cooling a laptop, but any other stable legs will do the job, even created from wood.
The objects can be anything from bottle caps to small card boxes or even paper. You need at least 3 or 4 of them, but 4 is better. Use your imagination or just look around. You can always find something if you look around.
Placing four small objects under the laptop at the edges often is enough to make sure airflow can pass without problems. If you feel that the machine is not stable enough when typing, try other objects or five legs.
We don't want to break our machine, right? We try to cool it down so it will work longer, without the risk of getting fried or melted from high temperatures. Play on the keyboard for some minutes, either typing fast or playing games. If you feel it's unstable, return to Step 2 or even Step 1.
The objects you used are still there, you can return them if you find better legs. Your machine is less noisy, less hotter and sometimes it looks cooler. This technique can be used at home, at the office, and pretty much every place where you have a stable surface to place your machine.