Clothed men and naked women... a classic (some might argue puerile) male erotic fantasy.Three of my favourites...

Edouard Manet,  Le déjeuner sur l'herbe ("Luncheon on the Grass"), 1862-63, Musee d'Orsay, Paris

Manet's masterpiece, the female figure in the foreground a combination of Victorine Meurent's face and Manet's wife Suzanne Leenhoff's body. But it is not the nudity that interests us here, but Manet's genius, not only as a painter, but in his capacity in his great works to engage and involve the audience. Emile Zola said "Painters, especially Édouard Manet, who is an analytic painter, do not have this preoccupation with the subject which torments the crowd above all; the subject, for them, is merely a pretext to paint, while for the crowd, the subject alone exists."

Julian Wasser, Marcel Duchamp and Eve Babitz at his retrospective at the Pasadena Museum of Art, 1963, Photograph

Well, we can allow the sublime Marcel his little jokes as he sits in front of The Large Glass contemplating his next move. After all, he considered most of his art an "amusement". For an analysis of his chess ability see Jennifer Shahade, who is a two time US chess champion. Jennifer has also turned the tables on Duchamp with her own video of her playing a naked male opponent while commenting on aspects of Duchamp's game. She said of the video "I guess being naked, cold and in a doomed chess position took away some of his natural cheer." The video can be found on the same page...

Josef Breitenbach, Dr. Riegler and J. Greno, Munich, 1933, Photograph

Arguably one of the most mysterious and therefore erotic photographs ever taken. All we know about it is that Riegler was Breitenbach's best friend and a journalist. There are several other pics from the same session if you feel like searching. What, you're leaving already?