Via Balloon Juice, the Ukulele Orchestra of Great Britainplays the theme from Shaft:

(At about a minute in, you might find yourself wondering: is it all instrumental? The answer is: no.)

Thesis: Insofar as one can generalize, the British sense of humor depends to a greater degree than most on exploiting utter incongruity presented absolutely deadpan, as though there were nothing the least bit odd about it.