Neil was Billy/ Dr. Horrible in Dr. Horrible's Sing Along Blog. He is Barney in How I Met Your Mother. And stared in Doogie Howser, MD. Neil has been in countless movies like Space Chimps. He hosted just about every awards show, the Tonys, Emmys, and Grammys in 2009. He will be Legend- (wait for it, and if your lactose intolerant i suggest you cover your ears) -dary for a long time.