This is pretty awesome:
In late 2004, Sal Khan began tutoring his cousin in math using Yahoo!’s Doodle notepad. When other relatives and friends sought his tutorial, he decided it would be more practical to distribute the tutorials on YouTube. Their popularity there and the testimonials of appreciative students prompted Khan to quit his job in finance and dedicate himself fully to what became Khan Academy, a free online resource with over 2,100 videos and 100 self-paced exercises and assessments covering everything from arithmetic to physics, finance, and history.
Khan was interviewed in a recent episode of PBS NewsHour:
Thanks to my friend Karen Go for giving me a heads up about this.