Solwise’s Homeplug AV device has mains passthrough so you can plug in other devices when you’re short on wall sockets.

We measured average transfer speeds of 34.2Mbits/sec in a home environment. Homeplug devices are adversely affected by electrical interference but with a multi-plug adapter attached with a laptop, TV and an energy-saving lamp inserted and a washing machine spinning in another room, performance only fell to 32.6Mbits/sec.

This plug isn’t backwards compatible with older Homeplug 1.0 devices, which means Solwise isn’t following the successful formula of Wifi vendors, where backwards compatibility helped success.