At least in the US, I think satisfying the 'purposes' requirement for non-profit status would be difficult. Just providing a free service isn't enough. Here's the IRS brief description:

"The exempt purposes set forth in section 501(c)(3) are charitable, religious, educational, scientific, literary, testing for public safety, fostering national or international amateur sports competition, and preventing cruelty to children or animals.

source: http://www.irs.gov/Charities-&-Non-Profits/Charitable-Organi...

UPDATE: I confused non-profit and charitable organizations. Disregard.