ChartLyrics is a lyrics database sorted by artists or songs. The Lyric API uses either a SOAP or REST interface to allow users and developers to access the database. The API provides 2 functions. SearchLyric to search the available lyrics and GetLyric to retrieve the lyric.
The site claims a "huge collection of hit lyrics." Your next music application can tap into the database with the new ChartLyrics Lyric API. You can use it to search in several ways and, more importantly, obtain the text that makes up the words to popular songs.