The final episode of The Archers - everybody falls of the roof undramatically, while Ruth looks at the devestation muttering "Oh no" to herself in her Geordie accent.
The final episode of I'm Sorry I Haven't a Clue - Hamish and Dougal are killed in a tube crash at Mornington Crescent.
The final episode of The Hitchhiker's Guide to the Galaxy - Arthur Dent discovers the ultimate question to the ultimate answer to life, the universe and everything, resulting in the universe being replaced with something even more bizarre and inexplicable. (My guess is that Arthur knows the answer, but Fenchurch knows the question, hence why they now exist in different dimensions).