Abraham Lincoln (maybe not an athiest but...)
"The Bible is not my book nor Christianity my profession. I could never give assent to the long, complicated statements of Christian dogma."

Einstein

Issac Asimov

Charles Darwin

Ben Franklin

I'm not sure if this answers your question, but there have been many great men in history who were athiests. But mainly as others have said, good deads should come from a person having morals, not because god told them too. I help people in need because... well hell it's our nature to help our brother. Why do people need to be scared into doing good. It's sad.