Shakers were an 18th Century offshoot of the Quakers. Somehow I thought there were more of them, but it turns out they really are an endangered religion. According to a PBS story from the Religion and Ethics Newsweekly program, there was still one Shaker community in September, 2010, and it had three members.
THE LAST OF THE SHAKERS — A COMMUNITY AWAITING DEATH: Only Twenty-two Left at Enfield Colony — No New Recruits, and Shakers Are Dying Off Fast — With Their Passing the Famous Sect Will Come to an End. (PDF)
From July 23, 1911