Mollom blocks around 95% of spam sign ups and comments for me, but it's still not absolute.
You can also block countries via GeoIP and apache, I've had some success with this because most bad requests come from China, Russia, and Africa (I've blocked many more as well). The obvious problem is that you block potentially legitimate users, and this may not be acceptable depending on your website.
Another great option is the quiz module for captcha (I forget the name) but you basically write your own short random questions with simple answers. No robot can get past those without human aid.
The final and worst bit that I'll add, is that there's no way to stop the spammers entirely. If they think they can profit off of your site they will spend money on paying people to sit there and answer captcha questions.
Best of luck.
On Tue, Oct 30, 2012 at 12:07 PM, Ken Robinson kenrbnsn@rbnsn.com wrote:
Try the spambot module. It checks email addresses against known stammers.
Ken Sent from my Verizon Wireless BlackBerry
-----Original Message----- From: Wayne Johnson wdtj@yahoo.com Sender: support-bounces@drupal.org Date: Tue, 30 Oct 2012 08:57:36 To: support@drupal.orgsupport@drupal.org Reply-To: support@drupal.org, Wayne Johnson wdtj@yahoo.com Subject: [support] Spammers
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