Environment Animation 1 - Take On Me

The 1986 music video by A-ha, Take On Me, is a very good example of how environment in animation can change a piece. It depicts a woman who falls in love with a man who is in a drawing. She gets teleported into a comic to be with him. After she enters, the owner of the cafe she was in previously thinks she ran out on her bill and she crumples the comic the girl is in and throws it away. Then inside the comic, characters with wrenches begin to chase her and the man down a corridor and she escapes out of the comic just before they catch up to them. He, however is left inside. She then runs home with the comic and she tries to flatten it. the man then appears in comic form in her hallway and starts to phase into reality.
This is a nice example of how animation can interact with the real world.