I love when celebrities do great things for random non-famous people. Unfortunately I don’t get to write about that nearly as much as I’d like, as it doesn’t happen with the frequency I’d like. But the latest one is really a doozie; a woman in New York City has found a bone marrow donor in thanks in part to the help of singer Rihanna. Attorney Lisa Gershowitz-Flynn, 41, found out she has an especially aggressive form of leukemia called Acute Myelogenous Leukemia right after Thanksgiving. Only one in five patients end up get a bone marrow transplant because it’s so hard to find a donor. Gershowitz-Flynn’s family and friends started a group, GiftForLisa.com, to try to get as many people to volunteer bone marrow as possible. Rihanna helped get the word out about Lisa’s desperate need for a donor, and the publicity she gave to her cause brought national headlines and a huge increase in the donor registry.

“When I heard about Lisa [Gershowitz Flynn]’s plight, my heart broke,” Rihanna tells PEOPLE exclusively. “I said, ‘I need to get the word out about Lisa right away.’ ”

Specifically, Rihanna is working with DKMS – the world’s largest non-profit marrow donor center to help raise awareness for the need for people to come forward to become donors.

[From People]

Lisa has luckily found a donor, even though the odds weren’t looking good.

“Today a 32-year-old guardian angel consented to be my donor, even though in all likelihood she has never met me and does not know who I am,” Lisa Gershowitz-Flynn, 41, a lawyer, wrote in an email to supporters Thursday.

“While we cannot verify the source of the donor,” Flynn adds, “this angel was most likely found through the efforts of my family and friends, as well as complete strangers who heard about my story and took it upon themselves to aid in the effort to find a donor.”

[From People]

DKMS says that not only did they find a matching donor for Lisa, but they registered an additional 2,000 people. Becoming a bone marrow donor is incredibly easy; all you have to do is have a painless cheek swab. Your DNA goes into the registry, and should you be a match for someone and wish to donate, a donor would undergo a minor outpatient surgery, which would extract healthy stem cells that would replace the cancer patient’s unhealthy cells. It’s an amazing way to save someone’s life. Several other celebrity moms got on board and championed Lisa’s cause, including Kate Winslet. Talk about good celebrities.

Here’s Rihanna at the Brit awards on 2/20/08. Images thanks to PR Photos.