QUOTE(gomi @ Thu 27th January 2011, 4:46pm)
This is not an exhaustive list. The Wikimedia Foundation would be within its right to sell the Wikipedia site to a for-profit company in exchange for a revenue stream. That for-profit company could shut down all user accounts and install advertising if they wanted to. The resulting revenue stream would (for a time) be very substantial. The Wikimedia Foundation would need to use the proceeds from such a sale for its charitable purpose.
And, in fact, it would probably have to do this if it wanted to monetize the site, because of the restrictions on charities receiving income from business activities. The wholly owned for-profit subsidiary would have to pay corporate income taxes, and distribute some or all of the retained earnings after taxes back to its parent nonprofit. (See also the Mozilla Foundation and Mozilla Corporation.) Arguably Wikipedia should have been set up this way in the first place.