Mac users interested in Fan control os x leopard generally download:
Manage the fan speed and activity when working on a Mac. Check the current temperature readings and increase or decrease the rotations speed of the built-in hardware fans, monitor the changes in conditions such as loading and cool runnings. Save configuration profiles.
SSD Fan Control is a fan management utility that comes in handy if you're dealing with a noisy hard disk fan. With its help, you can adjust the fan speed of the hard disk and optical drive according to your needs.
The interface of the utility consists of a single window where you see real-time information regarding the fan speed of your hard disk and optical drive.