I just used the Plex Unsupported App Store -
https://forums.plex.tv/index.php/topic/25523-unsupported-as-in-totally-unofficial-appstore/
to add shitloads of channels to my Plex Server, including ITV, Channel 4, MTV, VH1, Yify, BringThePopcorn (a Popcorn Time fork) and Full Movies on Reddit (a reddit community where people post links to full movies that are on YouTube).
This just increased the amount of things I can watch using Chromecast a hundred-fold. Between this, Netflix and BBC iPlayer, I don't need a fucking cable subscription. Just loaded up The Hobbit Part 2 in 1080p from the Reddit channel and it started streaming instantly with no buffering. fuck yeah.