The Lance Armstrong Foundation, which spends about $40 million a year on health programs and cancer research, is teaming up with Web-site operator Demand Media Inc. to launch a health-and-wellness Web site funded by advertising. The site, called "livestrong.com," is expected to go live this year.

As part of the deal, the Austin, Texas, foundation and Mr. Armstrong will take equity stakes in Demand Media, a Santa Monica, Calif., company run by former MySpace Inc. Chairman Richard Rosenblatt. Demand Media, a fast-growing but low-profile player in online social networking, was valued at nearly $1 billion by investors last year. Demand Media has raised about $320 million in the past 20 months from investors including Oak Investment Partners and Goldman Sachs.

Like Mr. Armstrong's foundation, more philanthropies are linking up with for-profit companies to raise cash and elevate their profiles. The Susan G. Komen for the Cure charity, which raises money to fight breast cancer, has more than 170 corporate partners, although the nonprofit isn't a shareholder in any of them. Other charities are using for-profit fund-raising tools like so-called investment term sheets and detailed growth projections to snag money from wealthy donors.