ThrottleStop - ThrottleStop is a lightweight application that was designed primarily for people who use their computers plugged into the wall and do not use the battery.
xScan - xScan is an application for viewing the behavior of your computer and Mac.
3DP Net - 3DP Net is an online repository full of all the drivers for your PC components.
Open Hardware Monitor - Monitors temperature sensors, fan speeds, voltages, load and clock speeds, with optional graph.
PCSpeedUp - PCSpeedUp is a powerful CPU performance analyzer and performance booster software.
smcFanControl - [Download] smcFanControl 2.