I friend (Pedro) pointed me in the direction of a photography manipulating tool called FaceFilter. It lets you change the facial expressions of a subject fairly easily by using a set of default templates.
While you would be able to do most of the tricks in your favorite photo editing software, FaceFilter will let you do the manipulations much quicker.
You can also discover some things about facial expressions that you might have realised before.
I tried the 7-day trial and had loads of fun with the “evil baby” below, see for your self.
 Original baby |
 Angry baby |
 Chubby baby |
 Making a face |
 Making another face |
 Mean baby |
 Not my baby |
 Sleepy baby |
 Young (?) baby |