According to slashdot, the english edition of wikipedia, a community-built multilingual encyclopedia, has now more than 100,000 articles online, after just two years of work!

Wikipedia is a website where anyone can edit any article at any time, and where anyone could use the content as they wish, if they follow the GNU Free Documentation License. Generally speaking, to re-use the content, you only need to give the same rights to your own copy, and you must credit wikipedia as the original source. That's it!