If you ever need to know the lyrics...

This widget displays the lyric for iTunes current track along with its artwork. The lyrics are saved in “Documents/Sing that iTune!” folder and you can also add your self-made lyrics in there. Sync the folder with iPod’s Notes folder to bring it. Option to save lyrics in music files is also available.

Apple Dashboard Widgets :: Sing that iTune!

p.s. Bradley, you'll appreciate the example on the landing screen.