Almost daily I've had to delete spam from DD - and sometimes it's quite vulgar stuff that I'd prefer didn't stay online for any period of time. Unfortunately no matter what I do to prevent bots, there are folk out there who are determined enough to bypass my efforts.
While I have no issues deleting spam on a daily basis, Jon and I may not see posts for lengths of time. If you would like to help out with keeping Digital DIY clean-cut and responsive to spam removal, please reply-post here and I will add you to the "Anti-Spam" group!
The call to duty will rarely present itself if a number of people are actively keeping an eye on content!
Cheers - I've trailed additional anti-spam questions (in addition to recaptcha), though they still slip through the cracks.
I may have just hit the nail on the head for a scalable solution for preventing spam.. Any new member to Digital DIY will find their posts are sent to a moderator queue. Their post can be approved by anyone in a moderator group, which includes everyone that replied to this topic (you all are now in the 'Queue Moderators' group).
The queue can be found in Moderator Control Panel > Moderation Queue. (MCP link at top left of any page).
After their first post has been approved, the new member will automatically be upgraded to a normal account. Free of moderation. Note - they need at least one post approved before this occurs.
While this is a small hit for new members, it prevents any one-time spammers with nothing of value for the site. Hopefully with a few mods keeping an eye on things, time taken for a post to be approved would be minimal.
NB - It can be compromised, although it takes a hell of a lot of effort.