Gimferrer has come up with some good Spanish ones. Another is Lovers/Amantes, about a sexually frustrated young soldier with a virgin girlfriend, who gets lodgings at the home of a beautiful widow...

In Une Liaison Pornographique, Nathalie Baye and Sergi Lopez regularly meet for sex in a hotel room.

Romance (Catheine Breillat), and Intimacy (Chereau) have sex as their main subject.

Of Freaks and Men (Balabanov) is an unusual Russian film involving spanking photos and erotica in St Petersburg.

Henry and June- in English- is about the erotic diaries of Anais Nin in Paris, and was the first film in America to have a 17 certificate. It stars Uma Thurman and Maria de Medeiros (Bruce Willis' "pot belly" girlfriend in Pulp Fiction). 
