Nicole Richie was the center of attention last night at a bash held inside NYC's Daniel restaurant. The cause for celebration was Nicole Richie's collection for Macy's Impulse, which will be in stores this September. Her limited-edition designs, 25 pieces in all, are inspired by music and will feature chiffon, zippers, and faux leather. Her husband, Joel Madden, wasn't able to attend, as he's in LA with their kids, Harlow and Sparrow. Joel's brother Josh, though, was able to make up the Madden numbers. Nicole also held court with pals like Charlotte Ronson and Teen Vogue editor Amy Astley. The party was the latest Big Apple event for Nicole. She also attended DoSomething.org and Bing's Summer of Giving event Tuesday, when we caught up with her. We caught Nicole Richie's Summer style tips and she also filled us in on why the day of giving back was so important.