Surf's Up. I didn't watch it when it first came out because it looked like "just another CGI penguin movie" (it was released around the same time as Happy Feet). I just watched it recently and it is one of the best CGI films I've ever seen. It had a very original concept (a surfing mockumentary featuring penguins), and had great writing and amazingly realistic acting (it had lots of improvisation). The animation was very lush, too. It's one of the only Sony Pictures CGI films I enjoyed (besides The Lorax). It seems pretty unnoticed, from what I've seen.