I've recently (last months) discovered Coursera - https://www.coursera.org/ - I can't tell you how grateful I am for the new worlds coursera opened for me, my learning hunger and my innate curiousity for things I love, don't ask me why.
I started with Introduction to Astronomy and the wonderful professor Ronen Plesser, I just love the guy and his ability to transfer not only his knowledge but also his passion and love for the universe. Unfortunately, it wasn't to happen! After the first week I lost valuable time with a pc crash and a heavy program, so I had to stop, for now... Buuuuut, me and many other miserable (at that time) students communicated with him and the course will be up and running again after some time. I am sooooooo grateful. :)
So, the first course I actually finished is Astrobiology and the Search for Extraterrestrial Life with professor Charles Cockell. I also recommend it since it is very interesting and the professor is a great lecturer. And guess what? I got it with 95.8% success and with distinction, of course!
Now I am running with three other courses and I am entering a fourth in a week. I may be crazy but I am a happy one. :)