Twiki care

[dougsweetser-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org (Doug)]

Hello:

I have a web site, and I could put a twiki on it.  How do people
defend against spam and malware?  I read on the web that having a
registration check box that says "I am not a robot"  is pretty
effective.  Thought I'd ask for people's experiences...

My guess is that approaches are web-framework specific.  Drupal has a
number of defensive modules I am using.
Doug