The Helldorado Days festival began in 1934 as a tribute to the Old West. The festival, which included a rodeo and parade, took place annually until 1997, and then was brought back by the city of Las Vegas in 2005. The proceeds from the festival help fund local children’s charities through the Elks Lodge.
Source: Sonya Padgett, “Raising Helldorado,” Las Vegas Review-Journal, May 13, 2010. http://www.reviewjournal.com/entertainment/raising-helldorado
The Sin Sity Sisters of Perpetual Indulgence are a Las Vegas chapter of men who dress outrageously as nuns in drag and do charity work to promote HIV/AIDs awareness. According to the Las Vegas Weekly they "The Las Vegas chapter of the Sisters — a vocational order of mostly male nuns in drag, with 30 chapters and missions around the country — take no government money and vow to help those in need, without judgment.
"The Shade Tree was established in 1990 as Jubilee Ministries and, at the time, had little more to offer than safety, shelter, and cots in the basement of Saint Luke’s Episcopal Church. In 1990, diocese members, Junior League of Las Vegas, and the City of Las Vegas collaborated to establish a permanent shelter. In December of that year, The Shade Tree opened in a building owned by Catholic Charities.