I heard this one somewhere, hope it wasn't here.
Little kid was ridding his bicycle along the side of the road in the bicycle lane when he was overtaken by a man on a horse. The kid stops to let the horse go buy when the horse stops and the rider ask the kid "where did you get that bicycle from kid?" Kid says, "I got it for Christmas, Santa Clause brought it to me." Man on the horse says in a smart ass manner "How about next year tell Santa to but a reflector on the rear of that bike!" Kid realizing he was dealing with a wise guy, asked the horse rider "Well where did you get that horse from mister?" Man says, "Santa Clause brought it to me" Kid then tells the man "How about next year, tell Santa that the dick goes under the horse, not on top!