Sensors at home
Several sensors at home gather temperature and other data.
Graphs are created with rrdtool.
House temperatures
To gather environment temperatures, 1-wire sensors are used with
DigiTemp software.
1-wire projects explains
more about the sensors.
Lightning strikes
The detector for lightning strikes is the Hobby Boards lightning strike detector and the counting is also done by DigiTemp software.
Server greenblatt
To gather system temperatures, lm_sensors is used.
To gather harddisk temperatures, hddtemp is used.
More about server greenblatt: Building - and maintaining - a new home server.