If you were designing Reddit today what would you do to prevent this kind of stuff?
1. Make the website invite-only. 2. Give out X invites to everyone. 3. Every user now has a reference pointing to who invited them. 4. Require that you must vouch for the behavior of the people you invite, and their behavior may impact your participation. 5. Use tree traversal and analysis for pruning bad sections of the population of users. (i.e. If you see a series of bad users, go up the tree to find the source an…
As you mentioned, it is too difficult to get off the ground with an invite system, but it may be interesting if an existing community became invite-only. Unfortunately the high risk of torpedoing your business is a deterrent.