A friend told me a comp in his warehouse had become unstable and asked me to look at it. He brought it over to my house one night (along with a six pack) and I popped open the hood. Solid black inside. And not because it was one of the way cool interior paint jobs. I took it out in the driveway and hit it with 100psi and a cloud of dust exploded from the case. I literally started coughing and had trouble seeing as I was standing close operating the air nozzle and got a lungfull and eyes full of that stuff.
I went inside after cleaning up his comp-u-box and looked in the mirror. I looked like I had been working in a coal mine. But the beer was cold. And the computer is still working fine (this is 7-8 years ago).