Argus Monitor - Argus Monitor is for monitoring and analyzing the temperature and the health status of the hardware parts of the system.

SpeedFan - Hardware monitor for Windows that can access digital temperature sensors located on several 2-wire SMBus Serial Bus. Can access voltages and fan speeds and control fan speeds. Includes technical articles and docs.

smcFanControl - [Download] smcFanControl 2.

Real Temp - Real Temp is a temperature monitoring program designed for all Intel single Core, Dual Core, Quad...

Open Hardware Monitor - Monitors temperature sensors, fan speeds, voltages, load and clock speeds, with optional graph.

AIDA64 - AIDA64 is a system information, diagnostics and benchmarking solution for Windows PC.