We introduce a novel data center design based on emerging 60 GHz RF technology that uses wires only to deliver power to its server nodes. Fundamental limitation of wireless data centers is that the maximum number of live connections in the network is directly proportional to the full volume occupied by the data center divided by the radiating volume of a single antenna beam. Consequently, we integrate wireless transceivers and switching logic within each server node and collocate them in cylindric racks to establish a semi-regular mesh topology. Our exploration of the resulting design space shows that while attaining comparable bandwidth, our wireless data center exhibits substantially higher fault tolerance, improved latency, lower power consumption, and easier maintenance than a conventional wired data center.