MIT OpenCourseware channel:
https://www.youtube.com/channel/UCEBb1b_L6zDS3xTUrIALZOw
Stanford online:
https://www.youtube.com/channel/UCBa5G_ESCn8Yd4vw5U-gIcg
Professor Leonard:
https://www.youtube.com/channel/UCoHhuummRZaIVX7bD4t2czg
NPTEL:
https://www.youtube.com/channel/UC640y4UvDAlya_WOj5U4pfA
Spark Summit:
https://www.youtube.com/channel/UCRzsq7k4-kT-h3TDUBQ82-w
3blue1brown:
https://www.youtube.com/channel/UCYO_jab_esuFRV4b17AJtAw
All Things Open:
https://www.youtube.com/channel/UCBhXFK70DbOU15N2BhDQVTg
etc., etc., etc.