Who Shot J.R?

Thirty years ago this week, 350 million people (83 million television viewers in America alone) tuned in to CBS's popular show Dallas to get the answer to one of the biggest cliffhangers in TV history. Who shot J.R?

The show, which debuted in 1978, was the first of its kind as a "primetime soap opera," and went on to run 12 full seasons.

The phrase became part of the lexicon, even becoming a popular T-shirt before the airing of the third season, which was riddled with a SAG strike and a contract dispute with Larry Hagman. Viewers had to wait an excruciating eight months to find out who shot the guy people loved to hate.

Cliffhangers have the amazing ability to keep people talking about their favorite shows during the off-season and (today) encourage sales of full-season DVDs, soundtracks and other branded apparel. And, of course, they have the desired effect of heightening the anticipation of the following season.

Dallas' "Who Shot J.R." is arguably the best television cliffhanger off all time, but what's your favorite television cliffhanger/plot twist?