A blonde, a red head and a brunette sign up with a tourist
group and chartered a double-decker bus to go to London.
There are only two seats left on the bottom of the bus and
only one seat in the top of the bus available when they
board.  They decided to take turns riding in the top and
flipped a coin to see who got the first turn.  The blonde
won the toss.

A couple of hours later it's the red head's turn so she
walks up the stairs, and sees the blonde sitting there
scared half to death. She's clutching the seat in front of
her so hard that her knuckles are white.

"What's goin' on?" the red head asks.  We're havin' a grand
old time down below." The blonde replies, "Yeah, but you've
got a driver."