What are some sad songs on the piano?

i really want to learn to play a sad song on the piano...do you have any...i know how to play "river flows in you" by yiruma...and i also know how to play "bella's lullaby" by carter burwell...so have any other sad songs..they arent really that sad, but yea thats the closest song that i know thats sad on the piano...the rest of the other songs i know are all happy and perky...lol :D