Tyra Banks may have retired from modeling in 2005, but she's officially back! After 13 years, the 45-year-old entrepreneur came out of retirement to grace the cover of this year's Sports Illustrated Swimsuit Issue, and all we have to say is, "Holy hell!" Tyra is the literal embodiment of the phrase, "Age ain't nothing but a number!" Tyra also announced that she'll now be using the moniker "BanX" to mark her return to the modeling world. "I want to flip the script and go by my last name. I'm taking something familiar and making it new. I'm wiser now and thicker," she told Sports Illustrated. "BanX is me, but she's also every woman. BanX represents rebirth and that beauty boundaries only exist to be broken." In honor of Tyra's return, see some of her sexiest moments ever ahead!