[Plugin: Invisible Defender] Great, but used by itself, some spam registrations get through

I really love this simple plugin — it does the job in most of the cases.

However, there are still a few spam registrations that slip through.

I would recommend taking a look at two of the actions that SABRE takes to further limit these registrations:

• Unobstrusive tests to detect if registration is done by humans or not (e.g., too speedy?)
• Registration blocked if Javascript is unsupported by the browser

These would seem to go naturally with your approach.

You might be wondering why I don’t use SABRE instead — for some reason, I encounter too many bugs with it.

http://wordpress.org/extend/plugins/invisible-defender/