Q: How many Lisp programmers does it take to change a light bulb?
A: (((((1)))))

Q: How many Pet Shop Boys does it take to change a light bulb?
A: Two.  One to change it, and the other to stand still and watch him.

Q: How many APL programmers does it take to change a light bulb?
A: @<-!&i

Q: How many Leslie Crowthers does it take to change a light bulb?
A: Only one (thank God) but the light bulb has got to come on down first.

Q: How many Bruce Forsyths does it take to change a light bulb?
A: One to change it, to change it, one!  (thank god!)

Q: How many JCR meetings does it take to change a light bulb?
A: "Surely there are far more important things to be discussed, such as the 
   plight of milk-bottle-top collectors in Nicaragua?"

Q: How many hacks does it take to change a light bulb?
A: One, as long as you'll vote for him/her

Q: How many sit-com "stars" does it take to change a light bulb?
A: At least seven, including token ethnic minority, rebellious youth, senile
   grandparent, unreasonable boss/neighbour, attractive woman.  David and 
   Maureen are giving a dinner party for Maureen's boss and his wife.  The 
   light bulb in the kitchen blows, so David finds a pair of step ladders so
   that he can change it.  While perched precariously on top on the ladders,
   Jason (a neighbour's child they are looking after for a few days) chases the
   family dog Dumpy into the kitchen and knocks the ladder, causing David to 
   fall, tearing his trousers off on a protruding nail, and lands virtually on
   top of Jason, who starts crying.  The parish vicar choses this moment to 
   pay a visit, and he, Maureen, and Maureen's boss enter the kitchen to find
   Jason across David's knee being spanked heartily.  "Oh crumbs....!"

Q: How many Derek and Clives does it take to change a light bulb?
A: One (cunt).

Q: How many northern comedians does it take to change a light bulb?
A: One, but you may as well include his wife and mother-in-law, as he'll talk
   about them so much.

Q: How many perverts does it take to change a light bulb?
A: Only one - he/she wants to be alone with it. 

Q: How many members of a trades union does it take to change a light bulb?
A: All or none.

Q: How many comics freaks does it take to change a light bulb?
A: Twenty - one to change it and 19 to leaf through X-men 1-682 to find out how
   Mr Apocalypse did it (when Storm Shafter blew out all the light bulbs in his
   secret hideout)