Light Bulb - Teamsters

Q: How many teamsters does it take to change a light bulb?
A: "Twelve. Ya got a problem with dat?"

Lightbulb - Junkie

Q: How many junkies does it take to screw in a light bulb?
A: Two: One to roll it, and one to light it up.

Archaeologists to Change Lightbulb

Q: How many archaeologists does does it take to change a light bulb?
A: Three. One to change it and two to argue about how old the old one is.