Remember that cute colorful tunic Nicole Richie wore in March when she was spotted taking her kids to a birthday party in Los Angeles?Thanks to WhoWhatWear we now have an ID.Nicole's long sleeved tunic is a one-of-a-kind piece from NUI and is made from vintage fabrics.Similar styles are available here or at Ron Herman.Here is Nicole Richie's "Nui" collection consisting of vintage maxi dresses and