This isn't as exciting, but along the same lines, I once spied on the people repairing my MBP: http://ecritters.biz/applecarefacility/
It depends on a library called CocoaSequenceGrabber. I'm sure you can find it somewhere, but the first Google link seems to be dead. I also have no idea whether it works on recent versions of OS X.
A fan was making a lot of noise. (Not just the usual noise fans make when they spin up; it sounded broken, like it was grinding against something.) They couldn't hear it, and didn't fix it. (Later, I brought it back and asked them to please just replace the fan, regardless of whether they could hear it. They did.)