Doves on fire and Americans in jet packs: When opening ceremonies go wrong

Friday sees the start of the London 2012 Olympic Games - and to mark the occasion a lavish £27m opening ceremony will be held.

Directed by Danny Boyle, he and the organisers will be keeping their fingers crossed that there are no hiccups and the event at the Olympic Stadium showcases the best of Britain and gets the Games off to an impressive start.

But it's quite possible that things won't go as planned (especially when three cows, 10 chickens, and 70 sheep are among the cast) - and if it doesn't Britain's embarrassment will be witnessed by a global audience estimated in excess of one billion people.

Boyle might want to look away now then, as we trawl through some embarrassing opening ceremony moments.

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