The temperature sensors that I use to drive the freezer graph are in my garage, which doesn't have an easy way to run wires to the server room. I have a WRT54GL running DD-WRT configured as a bridge to the rest of my network. The problem with this is that the connection isn't always reliable. I used to have a simple script that read the temps and fed them to my main mysql server, but the connection would frequently drop and it would lose the temperature data.
Hygrosens manufactures a number of sensors for measuring temperature, humidity, light level, pressure. Their devices use a common serial data format for a wide variety of sensors, include 1-wire sensors from Dallas. This library reads the output from Hygrosens devices and passes it to a calling function as a hash. I have included an example that outputs the readings in human readable format, and another that stores the readings into a MySQL database.