Lust, caution (2007)
This was described to me as an erotic thriller. I usually don't like erotic thrillers, since they often fail being good thrillers (or being good erotic dramas). Luckily for me, this story was more of a drama about the events around Shanghai and Hongkong during Japaneze occupation, and focusing of some of the resistance groups while including some graphic erotic scenes.
Good flick, and Ang Lee always fascinates me in his way of chosing quite diverse stories and styles in all his movies.
Heat (1995)
Al Pacino and Robert De Niro as antagonists in a cop and bankrobber story, what's not to like? The first time I watched that classic bankrobbery scene, it felt like a greatly directed warzone between the robbers and cops. It's still a great flick, but Mann have done other great work that tends to get overshadowed by this: Manhunter (the original), Insider etc.
Heat will be up among the great classic heist flicks, though.