rtcvb32: Refusing to create threads with too many numbers in the subject (
as they tend to be phone numbers), and too much reused of known spammer keywords or duplicated subjects from the same person among ways to stifle spam.
Or my favorite method: Pay/Redeem to get in. It has worked for SomethingAwful for over two decades, it could work even easier for here, since there are several cheap as free games that could be redeemed as part of a litmus/sapience test. At least one of them would appeal to actual humans, you got Postal, Tyrian, OpenTTD, Eschaon Book 1, and several other choices!
Of course, this
may exclude users
too incompetent to operate a blanket, but that is a risk that I'd be willing to take, since we've all seen more than our fair share of people complaining about having to solve a simple thing such as "click on the every image that contains scenes from the broadway version of
CATS."