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.