For me I really do enjoy watching some of the Locking picking lawyers content and he is an expert when it comes to picking locks!
Another few are mental outlaw (although I think everyone knows of him here) and Steven Bridges who makes videos on card counting at casinos and he shows how much he wins/loses from playing
His breakdown of Wozmon was my introduction to him. He is incredibly good at explaining and breaking things down. I was riveted when I started watching.