Movie: Van Helsing (2004)

It's one of the more common CGI effects images out there, and it's always incredibly unrealistic: the extending, inhuman mouth. Mainly used with vampires, the protruding jaws and elongated teeth signify something that's very ready to horrifically chow down, like the otherwise sexy female bloodsuckers who provide a little positive eye candy in Stephen Sommers' altogether putrid Van Helsing. As you can see, the effect is more "Mr. Ed laughing" than "scary vampire ready to strike."