In my opinion, Light Yagami's death in the anime was one of the saddest deaths I have seen in a movie, show, videogame, etc. I do agree with many that he became an evil person but I think that is what makes him tragic: he BECAME evil. That scene where he sees a younger version of himself shows how peaceful he used to be and how his life could have been had he not used the Death Note. In my opinion, as soon as he thought "Someone... What do I do now?", he started to revert back to his old self. Sad that it was too late, as the damage he had done led him to his death.