iCoverArt is a useful iTunes utility which automates embedding album cover art into song files. Artwork is displayed within iTunes while a song is playing (open the Edit menu and choose Show Artwork).
You can print CD jewel case covers or album listings with the album artwork by simply choosing Print in the File menu in iTunes. If you have an iPod photo (or nano or video), the album cover will display while the song is playing.
iTunes has a built-in method of adding artwork to songs, but it requires you to add cover art to each album (or song) one at a time. If you have a lot of songs this quickly becomes tedious! iCoverArt will automate the process: it will scan your entire iTunes library and then embed cover art into songs which do not yet have any.
iCoverArt does not require an iPod. Of course, iCoverArt will also work great if you are using iTunes along with any type of iPod -- iPod, iPod mini, iPod photo, iPod shuffle, iPod nano, Motorola ROKR phone, or even the new video iPod!
iCoverArt is most useful if you have ripped your CD collection into iTunes, since you will not yet have cover art in those song files. (Songs purchased online from the iTunes Music Store already have cover art embedded in each song file.) iCoverArt can embed album cover images in JPG, GIF, PNG, or BMP format into song files in MP3, AAC (and .M4P), AIFF, or Apple Lossless format (.M4A).
Please note that iTunes requires the album cover art image to be embedded within each individual song file. There is no concept of "shared album artwork." iCoverArt helps by automating the process of adding the same artwork to many different songs.