The first step is to get all the tools. Your computer, a stapler (I used a stapler "gun"), office tape and a pincer of some kind:
Open the stapler and take out the clips. A stapler gun has coarse clips and that is good.
Use the pincer and remove about 2 clips
Use the pincer to bend the clips in a L-shape
Insert the clips into the fan exhaust of your computer:
Put some tape on it to put it in place:
Thats it! Now the fan is in your control! Well, to be specific the fan is not moving. And thats a good thing! For your ears! :)
I have used this construct for 4 months now, and I must say that the solution works! The computer gets a bit warm after a while. Really hot in the sun. I try to stay out of the sun and monitor the temperature with SpeedFan. Despite my solution I have never had any problems with instability.