I use Drupal for almost all websites I create. Spamming has been a major problem and when putting www.lifhaus.com.sb online, I have had to tussle with spammers. At one time spamming was so bad, the entire Lifhaus website stumbled to a halt and was offline for an entire night.
Ultimately I gave up and installed the Mollom module to combat this problem. Although I admit I am not a fan of subscription services, I am most grateful for what Mollom has done to allow me peace of mind while it goes on with what it does best, which is blocking spam.
Mollom is also a paid service and according to its website is only free for non-commercial websites. I guess it is reasonable to expect some return for the hard work they do at Mollom. However, I gather that the free service has limitations in that it can only scan a limited amount of comments for spam and act on them. But it has worked wonders for my websites and I am very thankful for the service. Affordability for upgrading services will be a major problem once the websites I create and administrator attract more comments and hits, especially from spammers.
But I can vouch for the effectiveness of Mollom. On Lifhaus, spam dropped from 250 per day to only 20 a day which thankfully is still within limits for my free subscription. I now also have our corporate website on trial with the service and will put all other Drupal websites on Mollom.
I hope the Drupal gods work on current Drupal modules for spam and improve them. On Lifhaus, I have tried all solutions provided and must admit that at that time, they were cause for grief and frustration both from my users and me as the administrator. I have had little to worry about since going onto Mollom.
If you can afford it and you are administering a high traffic website which uses a CMS that can cater for Mollom, consider using it. I just hope that the anti-spam systems developed for WordPress find their way onto Drupal too. On this blog I am using WP-Spamfree and it has also done an amazing job for me. Unlike Mollom, it is not a subscription service and can be configured to detect and delete spam silently. If only it worked for Drupal too!
thanks for this info bro hope will help alot