In favor of a Scrat movie:
The funniest thing about the Blue Sky coming attractions was this Rat-Squirrel scene stealer. As good as Ice Age was, every time Scrat was on screen he up staged everybody else. He is a force of nature.
He is the reincarnation of Wily Coyote without the need for a Road Runner. He is pure comic genius. More shorts, many more shorts, please and how about a feature with other characters with their own agendas and plots but told all from the point of view of the monomaniac Scrat?