Balotelli for sure in recent years. Him with Tevez workrate would be a frightening player. Mad Mario did have some terrific moments (Why Always He, Italy v Germany and a certain assist to Aguero) but he didn't always deliver. I found his behaviour to be puerile. That of an attention seeking child. A spoilt one too.
Anelka always struck me as being a wanker. Goals aside, he'd given up before he left for Turkey and his career finishing with an anti-Semitic gesture spoke volumes. Perhaps Jewish people haven't suffered enough over the years.