Light Bulb - Social Workers

Q: How many social workers does it take to change a light bulb?
A: Four. One to remove the bulb from the socket and take it away without checking whether or not there was actually anything wrong with it, one to accuse its owners of mistreating it, one to find somewhere else to screw it in for the next 6 months, and one to eventually bring it back and say it was all done with the light bulb's best interests at heart.

Light Bulb - Scrabble Players

Q: How many scrabble players does it take to change a lightbulb?
A: I don't actually know, but it's on a triple word score anyway.

Light Bulb - Futurologists

Q: How many futurologists does it take to change a lightbulb?
A: None. He just takes the old functioning one out when nobody's looking, just to be certain.