Adding Guests to Ignore lists
 

OK, I've done some searching and come up empty.

I run a small, long-established community forum. We've allowed Guest posting since our we first went on-line five years ago.

I'm looking for an option which would allow our registered users to ignore guest posts.

I've thought of a cron job that would convert unregistered guests into a limited registered user account... but not sure that's idea. I'm pretty positive this should be simple, yet I've not found an answer here or through several hours of Google fun.

Any suggestions?

Thanks!