Mega star Amitabh Bachchan, who turned 69 today, says one of the best ways to celebrate birthdays is to keep working. Despite completing 40 years in Bollywood, the ageing actor is not the one to rest on his laurels.

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He is busy shooting for Ram Gopal Varma's 'Department', despite getting injured on the sets of the film. He is also hosting the season 5 of 'Kaun Banega Crorepati (KBC)' on Sony TV.