Each computer you want to network needs its own HomePlug box, with an Ethernet or USB cable running to the PC and a power plug connected to the wall.

FORBES: Magazine Article

Kevin Bong, a Wisconsin-based security researcher and penetration tester, has developed what he calls the Mini Pwner, a spy computer smaller than a smartphone designed to be inconspicuously plugged into an ethernet port to gain access to a corporate network, feeding information back to a nearby hacker over its wifi signal.

FORBES: Hacker's Tiny Spy Computer Cracks Corporate Networks, Fits In An Altoid Tin