Which was the best uncomfortable scene you have ever experienced in a film?

For me, it was the nude fighting scene [NSFW] in Borat (2006), I remember being 15 with my whole family watching the film (I know, so convenient). My parents, who are pretty old-fashioned when it comes to movies, were really disgusted by it, so I was really forcing myself not to cry with laughter though I think it's one of the best scenes in comedy.