Every alias service hides your real address. Don't SPAM Me also tells you which company leaked it. It puts unlimited catch-all aliases on a domain you own. Type any address into a signup form and it starts working with the first email. When an alias gets mail from a sender other than the company you gave it to, you get an alert naming that sender, and the company goes on a Data Sellers list. Disable an alias and it rejects mail with a hard bounce (SMTP 550), so senders stop mailing it.