We're getting into summer in the Philippines, and I was just worrying how hot my Thinkpad R51e was running. Its 32 degrees in the room, and my CPU is running at a consistent 73 degrees, according to
cat /proc/acpi/thermal_zone/THM0/temperature
which seems a bit unhealthy. My motherboard fried itself twice last year, and I figure that might have had something to do with it.
Anyway, I started casting around for things to reduce the power consumption, and found this powertop utility, apparently developed by Intel. (http://www.lesswatts.org/projects/powertop/) You can download it and install it from the site, but I just did a quick
sudo apt-get install powertop
and that seemed to work pretty well. When you run it (with sudo powertop), it reports all the things that are keeping your CPU awake and suggests a few things you can do to consume less power. Even better it will make these changes for you, if you press the appropriate letter on the keyboard.