Hats with built in earphones are nothing new, but this new beanie from iThreeSixty takes things a step further by including a clear window that holds the iPod itself.
On the plus side, this does mean that you won't get tangled up in the earphone cable as you move around, but I think you'll find that displaying your iPod to the world introduces a host of new problems. For starters, thieves will be able to tell instantly if your hat is worth swiping off your head. Even if you live in a safe area, it's hard to look cool if everyone can see on the display that you're secretly grooving to the new Justin Bieber album. But most problematic of all, you'll need to pull off your hat to dial up any specific album or song.
The beanies sell for about $50, and are compatible with all iPod Nanos except the wider series 3. Some versions include an unspecified donation to AWARE, a group that supports breast cancer awareness.