9. Philips Arena, Atlanta
When billionaire Ted Turner, owner of the Hawks, opened the $213 million arena in 1999, it immediately transformed Atlanta's bland downtown and midtown areas. Giant business headquarters, revitalized parks and upscale restaurants opened in the surrounding areas, in addition to the arena's Hawk Walk, an entertainment-and-shopping zone that includes TV shows in every direction and basketball-shooting games. As for rock concerts, Elton John's sold-out show christened the arena in 1999, and U2, Madonna, Bruce Springsteen, Paul McCartney, Prince and Taylor Swift have followed. Why was it called Philips, and not Turner, Arena? Because the electronics giant paid $268 million for the naming rights. Turner sold it after five years.
Fun fact: Ricky Martin sold out the arena for a fall concert in 30 minutes just a few months before it opened.