Any time you copy and paste code, THINK!  It's almost always a sign of a mistake -- If you have information to duplicate, there are usually dozens of better ways to do it.
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I've seen clipboard replacements for Windows that do all kinds of snazzy things.  What about one that detects copy and pasting of anything more than a single symbol, it could have a little angry avatar of KentBeck pop up and frown at the programmer.
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However, cut and paste should be OK, since then the programmer is refactoring.
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See Also: ThereAreOnlyThreeNumbers, DataDrivenPrograms