I'm a huge fan of the lyrics capabilities of iTunes, but I was a little dismayed by the fact that Spotlight didn't include song lyrics in its indexing ... until Leopard, apparently!

I didn't try this on purpose, but I typed tech into the Spotlight search field, and together with the folder I was looking for, the search results also listed the MP3 file of U2's Zooropa -- the first track of the album with the same name. How could that be? I immediatly recalled the bit of the lyrics that goes 'Zooropa, vorsprung durch Technik.' So I typed in some additional lyrics into the Spotlight field. To my great delight, it's now possible to search into your iTunes lyrics library from Spotlight, provided that you have previously filled up your MP3s with the lyrics.