email verification -- not just syntax

[brendt]

I have a PHP form on my site that sends email. The spam-bots have found it, so I need to add verification. I wanted to add one of those little scripts that displays a text string as a graphic and makes the user repeat it in a field.

Every string I've tried in search engines just gives me a bunch of scripts that only check the syntax of the address (no "repeat this string" verifiers). Can someone please point me to what I'm looking for?

Free, of course, would be good. But not necessary.

[Rambo Tribble]

It sounds like what you are looking for is CAPTCHA: http://www.captcha.net/

Be sure to put attention toward accessibility issues.