A young hacker has created a smartphone application that makes it easy to police the police - by streaming audio and/or video into a system that strips your personally identifying information before posting and keeping a watch on police.

Khan Academy, with Khan as the only teacher, appears on YouTube and elsewhere and is by any measure the most popular educational site on the web. Khan's playlist of 1,630 tutorials (at last count) are now seen an average of 70,000 times a day -- nearly double the student body at Harvard and Stanford combined. Since he began his tutorials in late 2006, Khan Academy has received 18 million page views worldwide.