Email forwarding is very useful when managing lots of domain names, or different extensions of the same domain name.
Catch-All Email Forwarding services will forward all email to an email address from your new domain name (eg. email@example.com) and forward it to a mailbox of your choice (eg. firstname.lastname@example.org).
The email management of your new domain is so simple and cost effective when using catch-all email forwarding as you will no longer need to setup multiple mailboxes for each domain name at an additional cost.