The Telegraph on extras:
… (Ben Hur) features a trumpet-playing extra who forgot to take his watch off.
…(Gandhi‘s) funeral sequence alone required 300,000 extras.
In Gladiator, they used 2,000 live actors to create a digital crowd of about 35,000 people.
One big-mouthed extra working on Indiana Jones and the Kingdom of the Crystal Skull spilt all the film’s major plot points when he was interviewed by his hometown newspaper in Oklahoma, even though he had signed a nondisclosure agreement. A ‘furious’ Steven Spielberg then got his own back by cutting the extra’s only scene.