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Kaley Cuoco got her start on TV in
Quicksand: No Escape (1992) when she was just six years old. (We know this isn't a yearbook photo. But wasn't she cute?) She went on to star in
Growing Up Brady and the sitcom
8 Simple Rules (2002-2005) and is now a certified geek goddess, thanks to her portrayal of the sexy and hilarious Penny on
The Big Bang Theory. She's doing double duty as a nominee and host of the 2011 Teen Choice Awards.