Methods to prevent form spam

[ApocalypeX]

This is more of a general discussion on the topic of preventing spam via forms; what techniques you use and why they are effective.I personally, for things like contact forms etc prefer the "moderation" form of antispam. For example if someone submits a contact form to me on my site or any where, they cannot send another until I mark their message as not spam.What about you?

[[dx]]

Captcha style :)Now it's working to enable already disabled button if code match. I know we can change this on some browsers, editors etc. But I'll rewrite it