Brand new & unused, I've got 3 of these surplus orders kicking around, product code UBQ-UC-CK.

Detailed by Ubiquiti here Quad-core SoC personal cloud storage & network management tools.

PB retail is $159, so $100 would be fair wouldn't it? & $250 for all three.

IN THE BOX 

Cloud Key 
Ethernet Cable 
Micro Sd Card 
Quickststart Guide