Reccomended software for system temp?

What the title says, anything for keeping an eye on system/cpu temp?

SpeedFan - http://www.almico.com/speedfan.php

Puts the temp in your systemtray when minimizing (right click to exit).
About 3 weeks ago I had a system shut down problem. It had been going on for about 2 weeks. After about 15 or 20 minutes on the PC, it would just shut down. One time I had it idle for about 10 minutes and it just shut down all by itself. I figured either a virus or I need to clean out the desktop (which I still need to do anyways). After I put in SpeedFan it's never shut down since, no matter how long I've been on the computer or how many programs I was running. Probably had nothing to do with fixing the problem (did other things that I can't remember), but it's the first icon I click after starting the computer.