You might want to check Videostream for Chromecast ? There's both a mobile app that links to your PC and also a desktop app. Last time I checked, VLC also allowed casting of videos on your PC(although iirc was more iffy with subtitles, etc) though not sure if there's mobile support, and I believe there are also other paid apps that can be used to cast videos. If you're referring to seeing videos directly from a hard drive without a PC, a TV with usb support should take care of that (long time ago, I had even a Bluray player that had usb and was used in similar fashion to cast videos from a usb flash drive)