He wanted to win the no-bell prize!
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Three skunks fighting over a pickle
First dog: My master calls me Furball. How about you?
Second Dog: My master calls me Sitboy
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Two. One to hold the bulb and the other to rotate the planet.
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None, because people who glow in the dark don't need light bulbs.
Note: Topical to the Chernobyl Reactor disaster of 1984.
or