I've always loved Robert Ryman. One must see his work in person to really get it. There is so much texture and depth in his paintings. He may only use one color, white, but there's enough in it to make it interesting. In his painting, Untitled 1961, he uses thick oil paint on paper. His choice of support and media make each painting very different. I like that he has limited himself to one color and one format. It's forced him to be more creative and to explore further.