Today my jaw dropped with Khan Academy

I can't say I'm a heavy user of Khan Academy. I used it in the past to refresh some math and computer science concepts. I am, however, a mega-fan of Khan Academy and the entire MOOC movement in general. Last year I donated money to the Khan Academy foundation after I saw their fundraiser on my Facebook feed and today I can say that was probably one of the best decisions I have made last year. It wasn't a great deal of money, but everything add up, right?

Well, today I saw these two videos:

WOW!!!!1! Are you kidding me? That's the best user experience I've seen so far, and it's on a massively complex topic of figuring out how to make the math syntax we are all educated with at school, to work and be understandable by computers. Truly astonishing work!

But it goes further than that. My next thought was, how does a non-for-profit, with limited resources manage to pull that of? Why hasn't another company done that before? I guess the answer, at least in my head, is that Khan Academy pulled this amazing feature of because they care the most about providing awesome experiences to their students.