An amazingly enthusiastic guy who demonstrates his custom built laser cannons and other fun physics experiments. Really recommended and inspiring to watch.
https://www.youtube.com/user/styropyro
2) VoidRealms
Click on Playlists to see all his tutorial series. I've only gone through his C++ Qt series but it's really great quality.
https://www.youtube.com/channel/UCYP0nk48grsMwO3iL8YaAKA