None. Any changes will have to be implemented in software.
or
A whole synod. One to move that the bulb be changed while the others debate until the room spins.
or
The owner got tired of the (w)hole business!
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What does it matter? we're all gonna die anyway.
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A porcupine.
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Because they are black and white.
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One, if it knows its own Goedel number.
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That isn't funny!
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[De-Calf-Inated]
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The bartender offers him a warm smile and says, "For you, no charge".
or