I hadn't heard this story before, but it is well worth sharing. I read it on Richard Russell's Dow Theory Letters (subscription required.)
As Russell tells the story, one day someone asked Buffett: "Warren, let's say you're dead and lying in your open coffin. What would you like someone to say as they gazed down into your open coffin?"
Warren thought a bit and replied: "I'd like them to say: 'Look, I think he moved!'"