It took Wikipedia only a little over a decade to force the 244-year old Encyclopedia Britannica out of print — such is the power of a crowd-sourced product. To date, there are 21 million articles in more than 280 languages sprawled across the Wikipedia universe. The fact that all of this is available for free (and ad-free) easily makes it the crowd’s favorite source for research materials.
Sustainability of the site depended largely on donations from the public. At the last fundraiser carried out, the public donated $16 million to the foundation so it can continue doing its good work.