Danish stand-up comedian Nikolaj Wulff ( shared this photo of his pet guinea pig getting REALLY excited about finding a piece of carrot. I have the same expression when I run across a slice of cake. Carrot cake, of course. Via I Can Has Cheezburger?
Squirrel: I'm sorry to bother you but the bird feeder is empty. (A squirrel, my mother named Petey, once got on the porch railing and rang the doorbell because he wanted some peanuts!) Now I call all squirrels, "Petey"