FWDitOn is a site that allows users to submit and rate emails that they find interesting, and higher rated emails go to the top of the popular area. The idea is to allow people to see the most popular fowarded jokes and other emails, and there are some good ones on the site. An email can be added to FWDitOn by simply forwarding it to firstname.lastname@example.org – and you do not need to be a registered user to do so.
I was disappointed, though, not to find the kind of super interesting personal emails that eventually go public and are read by everyone. Perhaps the site will evolve to include those as well.
FWDitOn differs in a few significant ways from digg, but the concept is the same. In my opinion FWDitOn is a lesser site for not emulating Digg more perfectly. FWDitOn places new emails on the home page instead of the most highly rated stuff, and has users vote on emails with 1-5 stars instead of simply voting it up if they like it. Both of these features could easily be changed.
There are rumors that Digg will soon launch new topics that go beyond news and allow users to vote on many different pieces of information. When that comes, look out. Other sites using the Digg model for ranking content may be quickly swept aside.