What about mimicking? I can't stop mimicking people (famous and not-so-famous), cartoon and other characters, or sounds - I do things like mimic fire engine and ambulance sirens, birds, and even the irritating, monotonous recorded instructions on CTA trains (public transportation here in Chicago). I can sometimes keep this "in my head", but I often do it while in public, which tends to turn heads and embarrass anyone I might be with at the time. Does anyone else do anything like this? 
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Remembering that you are going to die is the best way I know to avoid the trap of thinking you have something to lose. You are already naked. There is no reason not to follow your heart.
~Steve Jobs