It's basically a snipe hunt or left-handed wrench

Cow tipping debunked

Urban kids know that cow tipping is a fun prank. Rural kids know that cow tipping is a hoax. Ever wondered which is true? The answer is in, and it is resoundingly: FAKE. Cow tipping is basically impossible due to physics, and the fact that cows will not stand idly by and wait for you to tip them over. 

Image courtesy Flickr/freefotouk