Retired Prof. Sebastian Thrun of Stanford University is hosting free, online classes. Applying takes two seconds.
I've taken an AI class he hosted before and have to say it was absolutely excellent.
Currently, he's hosting a course on programming a self-driving car and building a search engine. Pretty neat.
More info here.
There's also an MIT course on circuitry and electronics here.
These are all great and I'm really happy that people are doing this. Free knowledge. Mr. Thrun resigned from his position at Stanford in the name of free knowledge, I look up to that.