Britney Spears kicked off her Femme Fatale tour last week, and while she's on the road, she's also gearing up to release her brand-new video for her next single "I Wanna Go." The full video will be out on Wednesday, but in this sneak peek we get a look at Britney's badass side as she stands atop an NYC taxi cab and takes out all the photographers around her. Check it out!