The original class that started "MOOC movement" is now, 3 years later, available again @ Udacity platfrom. It is the same, but it has changed also: it is not completely free anymore: videos are available for watching, but projects and guidance are $150 / month, for 4 months.
When I attended the original class, it was a great motivation of unknown,
but trustworthy, coming from such great professors from Stanford and Google.
A great class!
It is interesting that commercial training, in particular Pluralsight with subscription model and focus on practical technology (vs "academic") appears to be getting more traction and money recently...
Here is my "class explorer" based on YouTube API, with integrated text and video: AI-Class Text
I have created this tool to help myself learning, while attending classes 3 years ago. Udacity still does not have similar feature!