LOS ANGELES -- Celebrity charity work has been around as long as celebrity itself.
"Beethoven was doing charity concerts," says Myrlia Purcell, founder of LooktotheStars.org, a website that tracks celebrity charity events around the world.
Purcell and her staff compiled a list of the most charitable stars based on the number of nonprofit organizations and events they support. Some have their own foundations, others lend their name and fame to multiple causes.
"Nonprofits say having a celebrity involved can make or break their events," Purcell said.
Good thing Annie Lennox is around. The 57-year-old singer and political activist is the site's most newsworthy star. A U.N. Goodwill Ambassador fighting HIV and AIDS, Lennox has made news with more than 200 nonprofit efforts in the past six years and supports 36 charities.
Elton John is next, supporting 45 charities, including his own namesake AIDS foundation, which funds 55 programs worldwide. Former President Bill Clinton, who's associated with 50 charities including his own foundation, follows.
Rounding out the top seven: Bono, Brad Pitt, George Clooney and Angelina Jolie.
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FILE - In this May 21, 2009 file photo, Annie Lennox arrives for the amfAR Cinema Against AIDS benefit at the Hotel du Cap-Eden-Roc, during the 62nd Cannes International film festival, in Antibes, southern France. Lennox is one of the world's leading celebrity contributor's to charity. (AP Photo/Matt Sayles, File)
FILE - In this Monday, Oct. 15, 2012 file photo, Elton John appears on stage at his AIDS Foundation's 11th annual Enduring Vision benefit, in New York. John is one of the world's leading celebrity contributor's to charity. (Photo by Charles Sykes/Invision/AP, File)
FILE - In this Sept. 23, 2012 file photo, former U.S. President Bill Clinton waves to the audience as he opens the Clinton Global Initiative, in New York. Clinton is one of the world's leading celebrity contributor's to charity. (AP Photo/Mark Lennihan, File)
FILE - In this Tuesday, Oct. 9, 2012 file photo, U2 front man Bono, and a founder of the charity, ONE International, arrives for a meeting with European Council President Herman Van Rompuy, not seen, at the EU Council in Brussels. Bono is one of the world's leading celebrity contributor's to charity. (AP Photo/Geert Vanden Wijngaert, File)
FILE - In this May 23, 2012 file photo, Brad Pitt poses for portraits for the film "Killing Them Softly," during the 65th Film Festival in Cannes, France. Pitt is one of the world's leading celebrity contributor's to charity. (AP Photo/Joel Ryan, File)
FILE - In this Feb. 6, 2012 file photo, George Clooney poses at the 31st Academy Awards Nominees Luncheon in Beverly Hills, Calif. Clooney is one of the world's leading celebrity contributor's to charity. (AP Photo/Chris Pizzello, File)
FILE - In this March 8, 2012 file photo, actress Angelina Jolie attends the Women in the World Summit 2012, hosted by Newsweek and The Daily Beast, at the David H. Koch Theater, in New York. Jolie is one of the world's leading celebrity contributor's to charity. (AP Photo/Evan Agostini, File)