In Poland it's very often simply called "ape" (often giving e-mail addresses), before I often heard "elephant's ear".
Some people in Germany call it 'Klammeraffe', which would roughly translate as 'an ape that clings to something' or 'spider monkey'.
Finns often call it "miumau" (meow meow) because it looks like a cat's tail.
Hungarians call it "kukac" = worm because it also looks like a worm.
I think I'm going to start calling it cygnus because it looks like the accretion disk of a black hole.
Witch makes overheard conversations quite weird, since apenstaart is quite a long word: «yea, that is em-dot-dee-ee-vee-ar-eye-ee-es monkeytail hotmail-dot-com»