What Sights Should a Girl See in Sin City?

It's a girls' weekend in Las Vegas, and one of us has never been to Sin City.

I'm trying to make sure that I plan out everything she needs to see while we are there -- Fountains at Bellagio, Eiffel Tower at Paris, Volcano at Mirage and the famous Las Vegas sign on the strip.

What other iconic things are must-sees in Las Vegas?