His New Year's Eve party, in "Do-It-Yourself Mr. Bean".
And the his method of repainting the room the morning after with one of his guests caught in the blast.
Near the ending of "Good Night, Mr. Bean" when he attempts to count sheep. He couldn't figure out how many sheep were in the picture, so he uses a calculator. The instant he gets the number, he nods and instantly falls asleep.
From the same episode, he attempts to get himself to sleep by watching a chess game on TV. After the end of the chess game, it spontaneously switches to a rock concert with loud music, startling and waking up Mr. Bean
In that same scene, tell me you didn't burst out laughing when he shot the lightbulb with a gun just to simply turn it off.
Oh yeah, and notice that he's also got dozens and dozens of spare bulbs in the same cabinet, implying that this is what he does every night.