Steam's In-Home Streaming feature has just left beta and is now available to all of the PC gaming platform's users. If you've a top-tier gaming PC in the bedroom, but can't be bothered lugging it to the living room for big-screen play, the feature will allow you to remotely stream games to a less powerful computer or laptop over your home network, with your input controls beamed back to the main machine.
To avoid lag and stutter you'll of course require a speedy web connection, but as long as your two computers are both connected to the same network and are both signed in to the same Steam account, you should be good to go, regardless of specs or even operating system. It's a free feature and supports OS X, SteamOS and Linux as well as Windows (though for best results, a high-end Windows PC should send the stream). [Steam]