I hate spam, (yes, I hate you fu***ing spammers) and we are always trying to fight spam here at webdesignshock, so, another technique that may be useful:  This is a pretty old technique, but I’m a bit susprised why it’s not widespread. The idea is to use a hidden field to confuse SpamBots, so, basically your users won’t have to fill any captcha: Simple, useful, powerful and works like a charm.

Maybe honeypot captcha by Phil Haack was one of the first attemps to solve this spam problem by using invisible fields, as I said, it’s an old technique but it still works. In his article you can find the approach and source code he used, is still valid. Later, Guys behind Londons web designs go deeper into this problem an presented some useful information about this technique, so you might can take a look to their article.

But in case you want something easy and ready to work, please take a look to a WP plugin that implements this approach. (we are using it now in our comment form ;) ).. so, give us some feedback and test the plugin.