Zune HD 64 Blue Atomic Edition.
These Zunes with the "atomic" design were given to Zune team members to celebrate the launch of the Zune HD. They're exceedingly rare, with only a handful known to exist. Most units are in red, with a 32GB capacity. Some are engraved with the name of the original owner in the upper-left corner of the back plate. This particular blue device is the only known one of its kind, with 64GB of capacity and no serial number on the back. Identifiable information has been censored for the sources' privacy.