A scene I've always had in mind for The Joker:
It's a theater. The production is Pagliache. However, instead of the usual actors, The Joker walks on stage. Now, everyone thinks he's just part of the show. He then takes out a gas mask and a remote control. He puts on the mask, and presses a button on the remote. An invisible gas eneters the room. The people in the audiance start laughing uncontrolably for several seconds, flairling and looking as if they're in incredible pain. And then they all die. Then, The Joker preforms the porter monologue from McBeth in it's entirety. He finishes, and takes a bow. When no one laughs (since they're all dead), he just walks off mumbling "everyone's a critic". As he walks off, we see the bodies of the actors backstage strewn on the floor.