The unrated film that pushes boundaries furthest comes from writer-director John Cameron Mitchell (Hedwig and the Angry Inch). His second feature Shortbus, shown at Cannes and Toronto film festivals, contains hardcore images of sexual intercourse (gay and straight), masturbation, S&M, an orgy, and a menage a trois with a unique rendition of "The Star Spangled Banner." To date, it has the widest release of any film showing actual sex even as its non-pornographic narrative concerns emotionally-challenged post-9/11 New Yorkers searching for happiness.

Shortbus, Raphael Barker, Sook-Yin Lee, 2006, © Think Film. Courtesy of the Everett Collection.