YouTube has had quite a year. Today it announced that all told, the site saw more than one trillion playbacks in 2011. Awful videos are, of course, ubiquitous on YouTube (the #1 video on the site for the year that didn't come from a major music label was Rebecca Black's "Friday"), but the most-watched science videos of 2011 are, as you can see below, awesome.
"Do not touch the water. There is nothing more irradiated than the water itself."