It came in at quarter past four.
or
The cow that jumped over the moon
or
Because he wanted sweet dreams.
or
Five. Four to decide which way the bulb ought to turn, and . . .
or
None, but it takes at least one to sit and pray for the old one to go back on.
or
Billllyuns and billllyuns. Light bulbs are part of the interstellar "goo" that pervades our universe; they are star stuff.
or