I have never used Digg but I've seen it on various websites. I first saw it on StumbleUpon. After reading the article I stumbled on, it said "Digg this". What is Digg? How do I Digg something?
Digg is a social news website, consisting of letting people vote stories up or down, called digging and burying. The readers get to decide what the stories are by "digging" the story up. Digg was originally popular because of it's creation of other social networking sites with story submission and voting systems. It has inspired other social networking websites, like Facebook, to add the "like" button - which is very similar to digging something.
After finding out what Digg is, I think it would be a great tool for procrastination and boredom, much like StumbleUpon and Facebook.