Honeypot field since Captcha not effective

Although the Captcha field works when I test it, we’re getting a lot of spam sign-ups, so apparently bots are now doing math quite proficiently. So I’d like to add a honeypot field or other more effective anti-spam technique. Is there a simple way to do this or will it need custom code — and if the latter, are there any examples to follow?

Thanks!

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