Anything else from Brady Haran is pretty fun and educational. Not exactly in the spirit of pedantry and sit-down-and-take-notes, but really fun and engaging (like all good teachers should be, I say)
https://www.youtube.com/user/numberphile
https://www.youtube.com/user/Computerphile
https://www.youtube.com/user/sixtysymbols
https://www.youtube.com/user/periodicvideos
etc...