Christina Aguilera performs at the Justin Timberlake & Friends concert in Las Vegas. The singer did a rendition of ‘Not Myself Tonight’ After performing at Justin Timberlake's charity concert in Las Vegas, newly single Christina Aguilera was still in the mood to party. The singer took her crew of dancers and close friends to Tao to blow off some steam. Aguilera sported a skintight dress and waved to the crowd from her skybox as the deejay gave her a shout-out, announcing that the "sexiest lady in the world is in the house." The crowd also snapped pictures of Aguilera, who stayed out until almost 3 a.m.