Britney Spears BSPEARSCONCERT0505_01.jpg You don't get to be one of the biggest pop stars on the planet without keeping tabs on what other artists are up to - so perhaps that's why we caught Britney Spears showing up to the Staples Center for Alicia Keys' big concert!

Brit did her best to keep a low profile as the security guards waved her through the back entrance and then out again after the show wrapped up. In fact, if she hadn't been riding in her big, white Escalade, we probably wouldn't have recognized her at all!

Still, we're sure Britney had a great time - after all, Alicia puts on one heck of a show! Wouldn't it be great if they got together to work on some music?