Discussion on avoiding spam in comments
I run a custom-designed and developed system on my webforms. While the implementation is typically specific to a site, CMS, forms plugin, or what have you, the concepts behind it are general enough to be applied anywhere you have a form. It doesn't prevent 100% of spam, but by targeting the primary behaviors spambots use it prevents the majority of spam on web forms. There's two basic behavior-blocking elements at play in it:
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