Guitar Players to Change Lightbulb

Q: How many guitar players does it take to change a lightbulb?
A: Two: One to change the lightbulb, the other to say, "I can do that."

Signal Processing Engineers

Q: How many signal processing engineers does it take to change a light bulb?
A: Three. One to Fouriev transform the light bulb, one to apply a complex exponential rotational shifting operator, and one to inverse transform the removed light bulb.

Torotonians to Screw in Lightbulb

Q: How many Torontonians does it take to screw in a light bulb?
A: Fifty-one to do it and the other forty-nine to proclaim it's the greatest event in the history of creation, a truly world-class bulb screwing.