Steve Martin

Day job: Comedian, novelist,

Collects: Modern masters

Collection includes: Edward Hopper, Willem de Kooning, Georgia O'Keeffe, Cy Twombly, Helen Frankenthaler, Roy Lichtenstein, Pablo Picasso, Eric Fishl

Fun fact: In recent years he's become quite an outspoken advocate for the arts, and even published a novel, An Object of Beauty, with an art-historical bent to it.