Good things are simple and come in small packages. If you wanted a plugin for your music player that finds and displays lyrics for your songs, Lyrics Plugin is a good answer. It's free, small (around 60 KB) and available for Winamp and Windows Media Player. You don't have to configure anything, the plugin works well out of the box.
The drawback of this plugin is that the lyrics database is not very big, so you may still find famous songs that don't have lyrics. But it's easy to add them.