If you grew up in the 1950s and 1960s, chances are you've seen his work in comics such as Famous Funnies, Buck Rogers, L'il Abner (which he ghosted for Al Capp) and Johnny Comet.

FORBES: Schwarzenegger's Sargent

As the New York Times pointed out earlier this month, as more legitimate galleries and auction houses sell art online, it has become easier for less scrupulous sellers to sell unauthorized reproductions or even forgeries of work by famous artists such as Pablo Picasso, Alberto Giacometti and Henry Moore.

FORBES: Jackson Pollock or Not? Avoiding Fakes in the Art World