"Gossip Girl" star-turned-rocker Taylor Momsen is back to her old ways -- by stepping out in as little clothing as legally possible.
The 19-year-old former child star was spotted in NYC today filming a commercial for Samantha Thavasa, where she was wearing little more than a leather blazer and matching, studded-bra.
The Pretty Reckless singer was also sporting her famous raccoon eyes and showed off her long legs in a pair of heels.
Pretty hard to believe this is the same girl who played Cindy Lou Who in "How the Grinch Stole Christmas" back in 2000.
What do you think of her transformation? Check out more Good Girls Gone Bad in the gallery above!