Warhol

Certainly everybody co opted him so heavily in the 70s and 80s he no longer stood out as a lone giant - there is literally almost no work of art from the era that doesn't bear his influence - but he was an enterprising auteur up to his dying breath, and continued to revolutionize rock, fashion, computer art, 'zines, television, advertising, and of course "the arts scene."

He was truly the hardest working man in show business and don't let anyone tell you otherwise.