It's about time to write something on that topic again and the story is about Munin (example) and TEMPer (USB Temperature Sensor).

I decided that I want to keep an eye on the room's temperature and I searched for the cheapest possible external (USB) Termal Sensor. That's how I get hands on one of these TEMPer termal sensors.
It turns out that the sensor is great for the job except it's installation under linux (Ubuntu) in my case.
So here are the steps for installing it under Ubuntu and adding a patched "sensors_" plugin for Munin.
First you need to install "temper_mon.pl"
1) sudo apt-get install libusb-dev
2) sudo cpan -fi ExtUtils::MakeMaker
3) sudo cpan -fi Inline::MakeMaker
4) sudo cpan -fi Device::USB
5) sudo cpan -fi Device::USB::PCSensor::HidTEMPer
6) wget -O temper_mon.pl http://www.svilen.com/temper_mon.pl.txt
(alternative: wget -O temper_mon.pl http://www.cs.unc.edu/~hays/dev/bash/temper/temper_mon.pl)
7) chmod a+x temper_mon.pl
8) run: sudo ./temper_mon.pl
(you should see temperature readings now)
9) sudo cp ./temper_mon.pl /usr/bin/
(this is needed for the Munin plugin)
10) sudo wget -O /etc/udev/rules.d/99-tempsensor.rules http://www.svilen.com/99-tempsensor.rules
or create file: /etc/udev/rules.d/99-tempsensor.rules
with this line inside:
SUBSYSTEMS=="usb", ACTION=="add", ATTRS{idVendor}=="1130", ATTRS{idProduct}=="660c", MODE="666"
11) sudo /etc/init.d/udev restart
Now you should have fully running "temper_mon.pl" script which will give you readings from the USB Temper device.
Next step is to backup and replace Munin's "sensors_" plugin in /usr/share/munin/plugins
1) sudo mv /usr/share/munin/plugins/sensors_ /usr/share/munin/plugins/sensors_old
2) sudo wget -O /usr/share/munin/plugins/sensors_ http://www.svilen.com/sensors_.txt
3) service munin-node stop
4) service munin-node start
Now wait 5-10min and you should have reading in your Munin graphics.

Enjoy!