News By TooFab Staff | 8/9/2011 10:14 AM PT Some of the biggest names in Hollywood weren't born with them. Take Tom Cruise. His name just sounds cool, unlike Thomas Mapathor IV. Kirk Douglas sounds like a name a leading man would have. Issur Danielovich Demsky? Not so much. Actresses change their names too. Natalie Portman and Olivia Wilde roll off the tongue much easier than Natalie Hershlag and Olivia Cockburn. We've picked 20 actors who have changed their names. Can you guess their identities? Click on the "Launch Gallery" button below to play along. How many did you guess correctly?