Acorn to Arabella https://youtube.com/c/AcornToArabella: They're building a 38' sailboat from stump to ship, then taking it around the world. Already 223 episodes in and very educational.

Michael Penn https://youtube.com/c/MichaelPennMath: Covering calculus, number theory and more. Classic black board lectures, highly enjoyable.

Andreas Kling https://youtube.com/c/AndreasKling: Livestreaming development on SerenityOS (https://github.com/SerenityOS/serenity)