The way to inexpensive x-ray machines

''It turns out that if you peel the popular adhesive tape off its roll in a vacuum chamber, it emits X-rays. The researchers even made an X-ray image of one of their fingers.
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He suggests that with some refinements, the process might be harnessed for making inexpensive X-ray machines for paramedics or for places where electricity is expensive or hard to get. After all, you could peel tape or do something similar in such machines with just human power, like cranking.''

Source here.