Valve has released Steam’s In-Home Streaming to everyone. This feature for Steam lets you stream the video and audio output of a game from a Windows host PC to Linux client (and other operating systems) while transferring the input from the client to the host. This allows for you to play games that haven’t been ported yet if you’ve still got a machine running Windows that is powerful enough to stream the game, or to set up a machine attached to your TV that streams from your desktop.
Word is that Linux will be added as a host soon. There’s a support article with more details and a community group to discuss the feature. Notably, most of the announcements are written, and the software was presumably also developed, by former Loki Software employee, Sam Lantinga.