Intel has been promoting their Wireless Display (WiDi) technology for quite a while now and we are starting to see some traction in the industry to include it in display devices and other types of components.
So what is Miracast? Wikipedia describes it as such:
Miracast is a certification program of the Wi-Fi Alliance based on their Wifi-Display specification. It defines a protocol to connect an external monitor or TV to a device, and therefore can roughly be described as "HDMI over Wifi", replacing the cable from the computer to the display
So what do you do if your notebook has this capability but your wall mounted TV does not? Actiontec has a product called ScreenBeam Pro that turns any HDMI connection into a WiDi receiver. Priced under $100, you can easily connect a laptop or android device to that screen or projector with an HDMI connector and wirelessly transmit your video/audio signal to that device.
Actiontec also has kits that will provide your with a USB transmitter that will connect your laptop that doesn't have the WiDi capability built in so that it will work with the receiver. This is a great solution for providing this capability.