First, let me say how much I like Redirection. This has not only helped us clean up 404 errors to improve our visitor experience, it has helped us identify security threats through the 404 log. We noticed a large number of /wp-login.php 404 errors which means the hackers were trying to crack our password. Yesterday, we got over 300.
Now, I've found a creative answer to these blood suckers which combines Redirection with WP Rename Login. I've changed the name of our login URL. That creates a 404 error if someone tries to use the standard WordPress login URL. I then redirected /w-login.php to a new page that basically laughs at the hackers (though what they do is usually automated).
Now, it would be great if I could get an email from Redirection when log files reached a certain number that I could define or one of the log files (specifically 404) has a 404 error for a URL I would define. Then, if a hacker cracked my new name to login, I could be immediately alerted that there was a 404 error on that page and change the login name again.