coconutID (was coconutIdentityCard) is just a small app that reads out where and when your Mac and your iPod were built by Apple. Just plug in your iPod while the app is running and it will show you the information about your iPod instantly.
What's new in coconutID
Added support Retina iMacs and OS X El Capitan (10.11)
Just a small tip to US users: the date reported is in European date order: day, month, year.
For the longest time I thought my machine was made during an interval between April and October, when I really was during the first week of March.