Miracasting - how the heck do I use it for non-mobile devices?

The Wikipedia mentions that I can mirror my laptop or PC, but seems  a bit light on actual details.

Plenty of adapters, but all seem to be for the TV-side of things, not for the push side ?

None of my laptops or PC's have Widi capability ..

Is there a USB adapter for the PC/laptop side of things ?

Basically wanting to replace a 10m HDMI cable from PC to TV ....