Steam has been testing in-home streaming in beta. Good news to those waiting on this to release. This service is available now for all PC users. Updates still to come for SteamOS, Linux, and Mac. This feature is part of the promised package for SteamOS.
Steam in-home streaming is a way to play games from your Steam library on a computer that might not have the specifications needed to run the game. Being on the same network is a requirement for both machines. This allows for users who might have a home-theater pc hooked to their television in another room to play all their games on television.
See the complete article at GameSkinny.com.