Bill Hammack is a Professor in the University of Illinois Department of Chemical & Biomolecular Engineering. It sounds impressive, but what's even more impressive is that he's managed to take a lot of the high-tech things that are in our daily life and make the technology that makes them run accessible to the average person. Bill has a YouTube series that breaks down things like hard drives, the CCD sensor in cameras, and even light bulbs.
It's interesting stuff, and educational. All my fellow gadget lovers should take a look at the videos. Check out the Engineer Guy here for his full repertoire, and check out the hard drive teardown below:
[Source - Engineerguy on YouTube]