Often used to reveal things for comic or dramatic effect. Could be described as a counter POV shot. Basically, the script suggests the camera come around 180 degrees to get a shot from the "other side" of a scene. For example, in the Something About Maryscript, Tucker is playing a joke on Mary in her office in one scene that the writers didn't want to reveal right away. They use a REVERSE ANGLE to show that he's got two tongue depressors in his upper lip to represent teeth. This reverse angle is used for comic effect.