It has been over a year and I haven't finished it yet, but I find it the most interesting. It's Harvard's philosophy course [1]

Also, intro to comp sci by Harvard's open courseware. Without these, I might've dropped out of comp sci in my second year [2]

[1] https://www.youtube.com/watch?v=kBdfcR-8hEY [2] https://www.youtube.com/watch?v=z-OxzIC6pic&list=PLvJoKWRPIu...