I was having a spam problem on a website I look after recently and thought I’d try an alternative to Akismet, since the latter now needs to be paid for on commercial websites. I installed Anti-spam, which uses a honeypot style trap to catch bots, and left on the core WordPress setting where problem comments are emailed to you, so as to keep an eye on things.
Well, the spam comments came in: all the usual rot, just now largely getting rejected (though notifications are sent to me by email) rather than marked as spam but still requiring me or my client to sort through them and delete them. I’m satisfied enough to switch the email option off and let it do its thing silently from here.
The honeypot technique won’t stop manual spammers (though there’s a paid version that claims to be able to ward off 70% of them) but it’s taken care of a good chunk of the problem. If it ramps up again, the paid version at $14 might be worth a stab.