Having a rather straightforward name like Stacy means I'm not really subject to a lot of nicknames. Stace is pretty much it, although a select group of friends call me Stac (back in note-writing days, a spelling-challenged friend who meant "Stace" actually wrote "Stac" - I know, it's a fascinating story). These 10 people presumably liked their alternate monikers more than the ones they were born with, and went on to use them when they became famous.
3. Sting. Gordon Sumner was just a guy playing the bass with a band called the Phoenix Jazzmen when he wore a sweater onstage that would change his life. The jumper (as Brits call it) had black and yellow stripes, prompting the Jazzmen's bandleader, Gordon Solomon, to call him "Sting." It stuck.
4. Miley Cyrus. If you're not a pre-teen, it may not be common knowledge to you that Billy Ray actually named his daughter Destiny Hope. She was such a cheerful baby that her parents nicknamed her Smiley, which was eventually shortened to Miley. She legally changed her name to Miley Ray in 2008.