I know of a couple of media center cabinets that get overheated by the big, old iron they use to serve up the files. Besides the fact that it's the size of a deck of cards, the low cuurent draw and the low heat output makes it the way to go. Oh, yeah, I forgot ...it's $35 !!! Gimpy.
Those motorhomes I'm having built will one day need some sort of temperature monitoring system for about 10 or so spots. I'm currently watching a Brit who has cobbled it all together and is selling the components. I'd like to pull in all the data and send an email alert if something goes out of range.