[jbay808]

I used to run a forum for an indie videogame with a small but passionate userbase. Unfortunately it was completely overrun by spambots to the point that moderators couldn't keep up and they drowned out the real posts. We had to shut it down.

[RyJones]

This is one of the reasons Begg Knives shut down his forums. We literally couldn't delete accounts fast enough.

[ValentineC]

When I used to manage web forums, I ask a hard question during signup and put the answer within the question itself (e.g. "hint: the answer is xxx").

This usually stops simple spam bots that are aimed at that particular off-the-shelf forum software.

[AQuantized]

Why not stop allowing registration except by manual whitelist? At least until the spammer lost interest.

[detaro]

Is that less friction than captchas?

[duxup]

How would that work?

Manually approve someone who registers ... then discover they're a spam bot?