[rendleflag]

I've done something similar for years, though without the intelligent spam filtering. Every site gets a unique email address that follows a specific patters (e.g. [e-mail]). Most of the sites don't sell or leak my email addresses. It has happened, but the majority of the email addresses I've generated (close to a thousand) do not get spammed. I'd say less than 1%. Most of the spam coming to my domains are to generic addresses like [e-mail] or to addresses I didn't populate like [e-mail].

[kevincox]

That's why the signature would be nice though. I get a pretty good amount of spam at basically randomly generated addresses. The signature allows you to drop all of these. Then you can block signed addresses that get sold.

Basically the signature ensures that only you can grant a "token", and you can do so without actually updating the state of your mail server. You only need to update the mail server to block an address that has "leaked".