- How many drummers does it take to screw in a light bulb?
- None, we have machines to do that now.
- How many bassists does it take to change a light bulb?
- None, the keyboardist can do it with his left hand.
- How many lead guitarists does it take to change a light bulb?
- One -- he holds the bulb and the world revolves around him.
- How many lead singers does it take to change a light bulb?
- Changes? Huh?