It is called LyricWiki. It already has over 200,000 songs.
ResourceShelf’s Kennedy gives it high praise:
“Contributors worldwide are welcome. Users are asked to keep an eye out for typos, vandalism, etc. While monetary donations are accepted, it basically runs as a free service via the generosity of MotiveForce LLC, a software company. There are a few unobtrusive text ads, but that is pretty much it as far as commercialism goes here ….
Navigation is super-easy. You can browse for lyrics by artist, album, song title, genre, hometown, label, or language. (The site is also available in French, German, Japanese, Spanish, and Swedish.) Or you can use the simple text search engine, which offers interesting possibilities -- e.g., I found 16 songs that contain the word 'woodpecker' in their lyrics.”