Lindsay Lohan was arrested for drunk driving in Santa Monica early this morning — her second bust in less than three months. According to the L.A. County Sheriff’s Dept., 21-year-old Lohan was nailed around 2:15 AM near Pico Boulevard and Main Street early Tuesday morning.Just last week, Lohan was quietly booked by Beverly Hills PD for an alleged Memorial Day weekend DUI crash. She was due back in court on August 24 to face charges of driving with a blood alcohol level greater than .08 and misdemeanor hit and run. Lindsay just turned 21 — legal drinking age — earlier this month. She’s been voluntarily wearing a SCRAM alcohol monitoring bracelet for the past couple of weeks, even flaunting the device during a recent beach outing in Malibu.