Well the fans in most laptops and in all Apple computers are controlled by the firmware. At this time, I'm not aware of any open firmware hacks that allow you to change the fan speed.

I just don't know why the fan kicks in at such a high speed. Seems pretty stupid to me, but people want fast computers that don't make sounds.
MacBook 2GHz Intel Core 2 Duo w/ 2GB DDR2 RAM & 120GB SATA 5400RPM HDD
Canon Rebel XTI
Google Cr-48 Beta Laptop