Email Verify is a PHP script that allows you to verify email addresses without storing anything in any databases. It will send users an email requiring them to click a link to verify their email before their email is added to whatever you want to add it to.
Email Verify uses secure SHA512 hashing validate email addresses meaning users cannot simply hotlink to the verification page and you can easily customise this script to work with your existing registration system or easily add verified emails to a newsletter database. This is programmed in an entirely functional manor allowing you to easily use the functions included in this script anywhere you want, these functions are fully documented.
This script includes a full HTML example using HTML5 email validation alongside a javascript validation fallback for older browsers. All data is sanitised to prevent XSS attacks.