Product review (5 stars): Works good to expose nefarious coworkers.
I bought this because my office is essentially a site located doublewide and the A/C unit, and thermostat, is located on the other side of the trailer in someone else's office.

And this dirty mother, my coworker, on the other side of the trailer with control of the thermostat, was trying to tell me that he wasn't monkeying with it.

This proved that he was.  Temperature swings of 72F to 80F.  I caught him in the act, setting the thermostat from a reasonable 72F to an oppressive 80F.

He is now on the bread lines, where he should be.