In the television series, Misfits, when the thunder stuck and everyone got their powers, why did the people get the specific powers that they got?
Is it what they actually wished for?
Pretty much. Powers are all related to what people were thinking of, or wanted. E.g. the "power broker" wanted to be a power broker, but not in the sense of super powers. The invisible guy wanted not to be noticed, the old lady wanted to be young again.