Hi there. I like the gadgets made by microclimate:
http://www.microclimate.co.uk/
here is the right page on Swells Reptiles:
http://www.reptiles.swelluk.com/quic...croclimate+evo
There are a number of models at different price depending how much control you want to have.
I have also used the older habistat thermostats which were analogue gadgets and very reliable. The disadvatage of the analogue models is that they can only do very limited functions.