Simple Human Verification

While doing some work that involved contacting webmasters to have them update information regarding our office, I ran across an innovative but simple approach to human verification.

In web form submissions, developers would like to avoid having spam bots from sending in thousands of forms with junk info, so they typically use a randomly generated graphic that humans can read (sometimes) and computers can't (yet).

This form is used by Michigan simply asks the user to do a simple math problem and type the answer in a form field.  Simple yet effective (for now).