On television, Fierstein was featured as the voice of Karl, Homer Simpson's assistant, in the "Simpson and Delilah" episode of "The Simpsons" and the voice of Elmer in the 1999 HBO special based on his children's book "The Sissy Duckling", which won the Humanitas Prize for Children's Animation. In 1994, Fierstein became the first openly gay actor to play a principal gay character in a television series when he appeared as fashion designer Dennis Sinclair in the short-lived CBS series "Daddy's Girls". Additional credits include "Miami Vice," "Murder, She Wrote," the Showtime television movie "Common Ground" (which he also wrote), and "Cheers," which earned him an Emmy Award nomination for Outstanding Supporting Actor in a Comedy Series. He sang a tribute to Katie Couric on "Today" on May 31, 2006, her last day as anchor. He appeared as Heat Miser in the live-action remake of "The Year Without a Santa Claus" in December 2006. More recent television performances include an episode of "Family Guy," in which he played an overweight, chain-smoking mother and an episode of the second season of the series "Nurse Jackie" in which he played a man whose husband is dying. He also gave the voice-over for Lily in the Last Cigarette Ever episode of "How I Met Your Mother" when she gets a sore throat due to smoking.