Kingish.com

Spam.  Don't you hate it?

I've just discovered an excellent (and free) PHP class for generating CAPTCHAS on the fly.  Written by Edward Eliot, it's simplified my attempts at controlling the masses of spam emails being generated by submission forms on my site.  It's called the CAPTCHA Image Generation Class.  Funny that!  And what's more, it does exactly what it says on the tin.  ;-)

He's also written an extensive article about it, for those wanting to know the ins and the outs of the code, which you can find here. 

Great stuff!