COmanage Registry can track email addresses, although it does very little with them directly (other than potentially verifying them). This document provides recommendations for how to store email addresses for different purposes in registry.
Registry Usage (in cm_email_addresses)
Address to render in a directory entry, especially for use in a "To:" or "Cc:" field.
Attach to CO Person with type "official"
Delivery location (eg: mailbox).
Attach to CO Person with type "delivery"
Address to forward mail to, perhaps if received at a display address or an acceptance address when there is no delivery address.
Attach to CO Person with type "forwarding"
Alternate addresses to accept for mail delivery or forwarding.
Attach to Org Identity with type "official" or CO Person with type "personal"