What are some good songs to just pound on the piano and belt along to?

I'm looking for some really pretty, mostly sad songs that are fun to just pound on the piano and belt along with. Things like "Grenade" by Bruno Mars and "On My Own" from Les Miserables and "Born This Way" by Lady Gaga. Does anyone have any other dramatic, sad songs? I know Born This Way isn't sad, but it's fun to sing too, so I would also like something like that.