The Chromecast was one of the few things I really liked made by Google. I always have one in my travel bag and it's basically like bringing your own home theater to the hotel with you. I had a time where I lived in hotels and AirBnB's for almost a year and this thing was god send.
They have some other device which they want to sell which will replace it, but that one is big and clunky, not meant for traveling: https://www.youtube.com/watch?v=lSSI_Ht6Mis
Thanks for mentioning KDE Plasma Big Screen it's an interesting attempt. It's written in Qt, like many of the TV UIs today anyway. I need to check it out.