I use Mollom and see 1-10 a week, but they are all legitimate in the sense that some real person actually went through the process of registering, even verifying their email address by clicking on a link sent to them. They then may proceed to spam comments. If I look at their registration pages they have even bothered filling in some of the name and address fields. We are a regional org so address outside NY of NJ are rare but they are from everywhere. There is no way short of inspecting every registrant's info to guess their intentions (good or bad) until they prove who they are by spamming. We do have a special state called registering that new registrants are in until they verify their email. They have no more access than anonymous until they verify so they can't spam as anonymous cannot post anything on the site. Of course if you want to buy something from the store or pay dues, then you are registered with no hassle. We have not seen anyone take this route to get access.