BSPEARSINCOGNITO10307_01.jpgBritney Spears BSPEARSINCOGNITO10307_15.jpgAfter a night of celebrating, Britney laid low, going incognito in this grey dress and hat in Beverly Hills Tuesday night. Showing off her toned legs, Brit stopped by a friend's house for about 10 minutes before returning home.

Photogs also say they spotted a tour bus parked at Britney's house -- could she be gearing up for a Blackout Tour???