Near the end while a man and woman talk in the park, the woman's nipples can be seen through her sweater.
A shirtless Joel masturbates in his bed (under the sheets) and we see his sexual fantasy of having sex with a girl (no nudity in both scenes).
Tom Cruise dances in his living room in his underwear and shirt. Not really inappropriate. This is also the most famous scene throughout the movie.
Joel wakes up in the middle of the night in his tighty whities and then decides to telephone a call girl.
Joel finds a girl in the shower in the beginning of the film. Through the heavy steam, her breasts and some of her buttocks shown.
A man removes a woman's dress (revealing her body) and kisses her. She turns around and reveals her breast and, briefly, her pubic hair. The two are then seen briefly having sex from behind with some visible thrusting. The scene ends with her on top of him, thrusting on a rocking chair (shown from behind). Genital nudity is not seen.
A man takes off a woman's underwear in a close up (no nudity). The scene is done clothed and in a shot showing them from the shoulders up. In slow motion, there is some thrusting.
In one scene, there is loud moaning from a couple having sex offscreen.
There are no sex scenes with prostitutes and their clients.