Forum spammers signing up non-stop.
 

I'm getting nothing but spammers signing up. In the profile field "Biography" they always enter "Man"

I always put each of these users email address in the banned list. On occasion I'll also put their ip address in the banned list too, but it's taking a long time to do this for individual members, when there are so many spammers signing up. I haven't got any normal members signing up in many days. What to do?