Just once I'd like to see "Fatal hilarity" written on a death certificate.
In 1660, the Scottish aristocrat, polymath and first translator of Rabelais into English, Thomas Urquhart, is said to have died laughing upon hearing that Charles II had taken the throne.
In 1782, a certain Mrs Fitzherbert is reported to have suffered from an attack of hilarity while she attended a performance of The Beggar's Opera. When Charles Bannister appeared on scene as Peachum, she burst into an uncontrollable laugh so loud that she had to be expelled from the theatre. She laughed continuously all night long and the day after and died early in the morning, the following day.
[Hat tip: xkcd]