Very cool - that would answer a lot of questions that show up here. It would also be a much more simple (compared to X-rays).

It's real cheap technology too (assuming this is what you mean):
http://www.dealextreme.com/details.dx/sku.91

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Yeah, that one is the laser I use, it's so awesome it's hard to put into words. of course all my toys say they aren't really toys, like my power tools and my NDFeB magnets, but you can get yourself killed in all sorts of innocous ways, so I don't mind the apparent risk.