Nerdy viewers of The Big Bang Theory would've revolted if Howard fantasized about any random guest actress on the show. Casting directors had to be cautious in selecting the perfect dream girl for the demographic. Enter: Katee Sackhoff.

While starring as Captain Kara "Starbuck" Thrace on Sci Fi's Battlestar Gallactica, Sackhoff also voiced a female marine in Halo 3, a number of characters on Robot Chicken, Bo-Katan in Star Wars: The Clone Warsand campaigned for Resistance 2. Coming up, she's taking on a leading role in Riddick.