Of all things, Outlook. It lets you create aliases that you can delete at any time. By "alias", I mean entirely separate @outlook.com email account. Once it's

Of all things, Outlook. It lets you create aliases that you can delete at any time. By "alias", I mean entirely separate @outlook.com email account. Once it's set up, you can either - Create a rule ("Recipient contains", <new email account>) to to for example delete email sent to that account, if you don't want to lose the alias - Delete the alias - I do NOT know if you can reregister it in future, if it gets reserved, or what happens here. Aliases: outlook.com > Gear icon (top-right) > Options > "Create alias" - 2nd from the bottom, first section Rules: Gear icon > Manage rules NOTE! You can also setup forwarding w/ Outlook, but Options > "Manage forwarding" mentions "Please sign in at least once every 365 days—otherwise your account looks inactive and could be deleted."