at my old local, a fat kid with a bright green helmet used to show up and lurk with board in hand on top of the deck. He always had a younger friend who he would be talking skate shop with, though both never skated. Everyone called him Helmet, as in "Fuck off Helmet!", "Get the fuck out of the way Helmet!", "Helmet you fat fuck!"
whenever I saw him at any other park with completely different locals, the nickname and response were exactly the same. anybody that skated in Sydney around 2005-2007 will probably know who I'm talking about.