neat! Here's another one for ya: barnacles have the longest penis relative to body size. It can be 25X the length of their entire body. But this makes sense given they are sessile and can't move off to find a mate. But imagine extending that and feeling around blindly for a suitable mate : Barnacles are also hermaphrodites, BTW, to eliminate the possibility that the only conspecific within reach is of the same sex! Doh!