I'm more amazed at what Pinky says compared to the things Brain thinks of >_<
There were one episode where Brain almost conquered the whole world by mind controll or something, but pinky forgot a little detail and the whole plan was a failure, as always
What I can still recall of Animaniacs. Slappy and Skippy Squirrel deciding to go after Siskel and Ebert for a bad review. Yakko, Wakko, and Dot driving the Grim Reaper crazy after Wakko died winning a meatball eating contest. Of course the running gag with Chicken Boo "He's a chicken I tell ya, a giant chicken!"