Pardon me for acting as part of the "comedy police" but the thread title is, after all, "tell me a joke". A joke is meant, is it not, to evoke a sensation of amusement in the tellee? This might range from a full-throated guffaw to the merest hint of a smile, but some such response is, nevertheless, an essential element of any joke. A joke may tickle some folks and leave others cold; its intent is the same and it is still a joke, successful or not.
I have, however, yet to hear of anyone actually laughing at a riddle. A wry appreciation of its cleverness, perhaps. Maybe even a gasp of admiration at the cleverness of the wordplay. But - is it a joke? Is it fυck. Is it on topic in a joke thread? I refer you to my last sentence but one.