xkcd is the webcomic creation of Randall Munroe, an extraordinarily popular web presence whom we feature regularly on EarthDesk. He draws on science themes often and has been nominated for a Hugo Award twice, thanks to his loyal science fiction fan base. He enjoys creating different ways of looking at our planet. But you know that by now.
The xkcd website is here.
Read more about Randall in this New York Times feature.