http://www.spyderrobotics.com/home/products.html

I would get at least a Herpstat basic, but a Herpstat 1 would be a better choice as it fails off instead of off (meaning if something goes wrong it turns the heat off instead of letting it blast and burn your snake). If (when) you move up to a rack, you won't have to invest in another thermostat. You an also look into Reptile Basics thermostats (reptilebasics.com) but the prices are comparable to a Herpstat.