I was interested in monitoring the temperature of my fermentation bucket for my latest home brew.
To keep the beer at a constant temperature I got a large 60L plastic storage container from B&Q, filled it with water and immersed the fermentation bin in it.
To keep the water at a constant temperature I bought a fish tank heater.
Also in the water was a waterproof digital temperature probe that I got from ebay for about £2. This in turn was connected to the RPi.
The temperature probe logs the current temperature to a file. This file can be read by a program and the temperature published to a website.
