While stitching up the hand of a 75 year old Devon farmer, who cut it on a gate while working cattle, the rural doctor struck up a conversation with the old man. Eventually the topic got around to Gordon Brown and his appointment as Prime Minister.
Well, you know," drawled the old farmer, "this Brown fellow is what they call a fencepost tortoise." Not being familiar with the term, the doctor asked him what a fencepost tortoise was. The old farmer said, "When you're driving along a country road and you come across a fence post with a tortoise balanced on top, that's called a fencepost tortoise."
The old farmer saw a puzzled look on the doctor's face, so he continued to explain, "You know he didn't get up there by himself, he definitely doesn't belong up there, he doesn't know what to do while he is up there, and you just have to wonder what kind of idiot put him up there in the first place.
(probably a very old story, but not one I can remember having heard, but very true nonetheless)
Many a true word...