Seven. One to install the new bulb and six to figure out what to do with the old one for the next 10,000 years.
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Well, first let's talk about the concept behind this whole "light bulb" thing.
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A stick.
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Two. One to screw it in, and one to stab the other in the back and take all the credit.
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I'm going out tonight!
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None. There never was any light bulb.
Notes: Probably the only really good light bulb joke of 1984.
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