GoAway (Drupal Module)
GoAway is a dirt-simple, light-weight "Ban By IP" module for Drupal 6 and 7. It works by redirecting offending anonymous users to a page or URL specified by the admin. The module possesses the following features:
GoAway fills a void in Drupal 6, especially for high-traffic sites which can't (or don't want to) bear the combined load of the Statistics and Tracker modules. The entire purpose of GoAway is to make IP banning as easy as editing a comment.