New anti-spam trick: Check if your comments came from open proxies before even beginning to process them. I like Kitten’s suggestion that this should go in before the wp-comments-post.php in WordPress. This trick can be used in non-Wordpress blogs as well. Via: PhotoMatt
i converted john’s hack into a plugin called ip blocklist.
It’s a shame that it uses a relay blacklist and not a proxy blacklist. Not one of the open proxy IP addresses that I’ve gotten spam from is in the RBL.