A few times at home with my parents, I've used the 'chrome-cast' functionality to view Youtube controlled from my laptop, without any cable hassle.
The same thing with Plex worked, but finicky. Somewhere between linux, plex and the TV, there is some compatibility problem.
That 'cast' functionality has improved and enhanced my life more than I expected. It saves significant time, hassle and stress to be able to connect to either of the two main screens in my house from my laptop when I want to show someone what's on my screen (remote desktop in reverse is how I think of it). No redundant searching, or going to the trouble of sending someone a link. Just cast and it's there.
However, it works best for images and text-- video or graphics tend to have more issues, and there is definitely a lot of lag, as with remote desktop.
Some web-apps, like youtube, do the casting for video in a more complicated manner.
Rather than actually doing the 'remote desktop in reverse' they essentially instruct the Smart-TV to go to the same video end-point and start streaming. Thus, none of the rendering, decoding or even downloading will be done on your laptop.
This is slightly worse from a control perspective, but quality wise it is great.
