Nerdy Jokes

[Remiel]

This thread is for excessively nerdy or geeky jokes.  For example, one of my all time favorites:
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An engineer, a physicist, and a mathematician are tasked with the following problem: invent a Perpetual Motion Machine (a machine which, once set in motion, continues to stay in motion without outside stimulus, in defiance of the laws of thermodynamics).  The engineer takes one look at the problem and declares the solution to be impossible.  The physicist says, "you don't know that, you just say it can't be done because no one ever has."  The mathematician sits down, takes out a sketchbook, and starts scratching out equations.  He does this for a very long time and goes through several sheets of paper.

Finally, several hours later, he stands up and triumphantly exclaims, "Eureka! I've got it!  We just have to redefine the universe such that entropy does not exist."