I work on a device that evaluates "cards" (credit-card shaped containers) which contain blood samples from patients.
We recently sent out a bunch of files with strings to be translated. The translation company is a giant shop where the workers have no real sense of context. When this kind of enterprise collides with science, hilarity ensues.
In one language (spoken in the Middle East), the phrase "card identification" (i.e. to which patient does this card belong) was translated into the equivalent of "driver's license".
In another (spoken in Asia), the term "well" (i.e. a small cell to store fluid) was translated as "feeling good".