I'm also checking the temperatures on my servers.
(harddisk, cpu, mainboard,..)

Assuming you run linux, you should be able to grep the temperatures in the files at /proc/acpi/thermal_zone/*
There should also be some modules at cpan.

I experienced temperature problems from time to time,
which leaded to strange problems (segfaults, the big bytecrunsher,...)

The last time I met the bytecrunsher, there was to much dust on the cpu's cooler..