How Do I Prevent Junk Account Creation?

Question

I want to allow readers of my WordPress-driven sites who comment frequently the ability to sign up and have their own account on the site. However the ratio of actual readers versus spam scripts using the sign-up form is something like 1:100.

Is there a reasonable solution for preventing these bogus accounts from being created while still allowing reader sign-ups? Last I looked, I couldn't find anything for account creation like what spam-prevention measures are available for comments.

Answer 1

Sabre is great plugin, it allows me to block dozens of spam user registration per week.

It has also many useful features to control the style and captcha's complexity.

Answer 2

I know of some sites using TruBar successfully.

Is OpenID not also an option? I doubt the robots will know how to register for that?