A garbage truck.
or
First they have to agree on which is better; the analog bulb or a digital bulb.
or
It's not a shrub, it's a lemon tree my dear Watson.
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"The way you make me feel, it really turns me on!"
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None. Agnostics question whether electricity really exists.
or
None. They will never find a bulb that burns as brightly as the old one.
or