smcFanControl lets the user set the minimum speed of the build-in fans. So you can increase your minimum fan speed to make your Intel Mac run cooler. However in order not to damage your machines smcFanControl doesn't let you set a minimum speed to a value below Apple's defaults.
Requirements: Intel Mac / OS X 10.5 or higher
Compiled version: http://www.eidac.de/smcfancontrol/smcfancontrol_2_4.zip
License: GPL 2