iPod icons from Fast Icon
The iPods minimilist and shiny design makes it the perfect subject for a Mac OS X style icon, and it seems that everyone has produced a set. The most recent being Fast Icon.
They've produced a set of nine icons covering all the currently available iPods (including the U2 iPod) and a "web" iPod which uses an overlay of Apple's iDisc icon. All of them are rendered realistically, much like every other iPod icon that is available.
Hopefully we'll start to see some more interesting iPod icon designs soon because these don't offer much over the default icon, other than being able to match the icon to the actual model that you own.