Drigg is a powerful Drupal module written by Tony Mobily, that allows you to promote stories automatically based on your users’ votes. Unlike other Drupal and non-drupal solutions, you can do this with amazing simplicity.
For a test site, see
There is no need to use Pligg for Drupal lovers. You can have a digg like mechanism right on your drupal site while enjoying all other powerful features of drupalv