I've been receiving spam in my support forum. It wouldn't even be for the same thing either. It would always be something different and random. So far I have banned the IPs that have posted it and increased my forum's spam filter, but I'm almost positive it'll come back. Any ideas on what I can do?
I would recommend adding a Anti Bot Question to your phpBB3 forum. I run a personal forum for a small game community and I have never used a CAPTCHA. However, I have used a Anti Bot Question and so far it has worked wonders. In just over 18 months, we have had not 1 single spammer register.
I second the suggestion of using an antibot question. That with recaptcha won't be perfect, but will do wonders to keep the cruft from your forums.
Most of forum customers we host have both setup and find the slightly longer registration a fair trade for reducing spam. Another suggestion is to make the Anti Bot question relevant to the forum if possible as most forums employ a very simple math problem.