What spam plugins work for you ?

[__JJ__]

Way over the top but for extreme problems I found this by accident
plugins involved:
Date of Birth on Registration Created by MattRogowski
Invitation Plugin Created by cfillion
Registration Security Question Created by - G33K -
MyTheme Created by Terrorz

theme
Twist-SD Created by Johnny S

I already used all the plugins then installed Twist-SD & noticed the MyTheme still worked but others did not using the theme. Since they are active but don't show up on registration page the fields can't be completed & you can't register. I then set Twist-SD as default with a notice on that theme to use MyTheme to change the theme before registering

Like I said for extreme problems & am sure could be adapted to any theme & to Johnny S it is a great theme just a little hard to work with