(Mental Floss) -- David Letterman has been in the news for helping police foil an alleged attempt to blackmail him, but the late-night star is hardly the first celebrity in this position. Celebrities ranging from Cameron Diaz to Elvis Presley have been victims in past extortion schemes Here are a few brazen and mostly unsuccessful attempts to blackmail famous people. 1. Bill Cosby  Bill Cosby may be one of television's most famous family men, but a 1997 extortion attempt tried to claim that his family was a bit bigger than anyone knew. That year, a 23-year-old woman named Autumn Jackson attempted to extort $40 million from Cosby in exchange for not telling the press she was the star's illegitimate daughter. While Cosby admitted that he had an affair with Jackson's mother and had given the woman and her daughter over $100,000 in support over the years, he flatly denied being Jackson's father.
@highlight
There have been some unsuccessful attempts to blackmail celebrities
@highlight
Bill Cosby was a victim in an attempted extortion plan for $40 million in 1997
@highlight
A photographer tried to blackmail Cameron Diaz with explicit photos of her in 2003
@highlight
Elvis Presely was reportedly a victim in blackmail in 1959 with pictures,  tapes
@placeholder, who was convicted along with two accomplices, received a 26-month prison sentence.