By Len Brown
4:30 PM PDT, July 20, 2011
Since there was already a more famous Michael Douglas in Hollywood, Keaton took notice and changed his last name to what you see today.
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Michael Keaton (Michael Douglas)
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Since there was already a more famous Michael Douglas in Hollywood, Keaton took notice and changed his last name to what you see today.
Whose real name is Michael Douglas?
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Tom Cruise (Thomas Cruise Mapother IV)
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Before the world knew the 'Mission: Impossible' star, Tom Cruise was born Thomas Cruise Mapother IV.
Whose real name is Thomas Cruise Mapother IV?
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Natalie Portman (Natalie Hershlag)
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The 'Black Swan' herself came into the world as Natalie Hershlag due to her Israeli heritage, and went to the more flowing Natalie Portman.
Whose real name is Natalie Hershlag?
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Olivia Wilde (Olivia Jane Cockburn)
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The stunning actress who's virtually everywhere in Hollywood nowadays didn't always have the untamed last name. Olivia Jane Cockburn was her name before she went with the more suitable Olivia Wilde.
Whose real name is Olivia Jane Cockburn?
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Steven Tyler (Steven Tallarico)
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The Aerosmith frontman and "American Idol" judge went by Steven Tallarico before replacing his last name with Tyler.
Whose real name is Steven Tallarico?
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Celebrities Who Change Their Names
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Wouldn't we all like to change our names? Well, some of us would, but a majority of the name changers that are around today come in the celebrity variety. Take a look and guess some of these famous celebs who have made the big switch!