Fully useful aliases in O365
In Office 365, like in any other hosted exchange service, you can create multiple aliases for your account. You just need to (while logged into OWA, you must have admin rights):
Go to Options -> See All Options… Choose Manage My Organization. In Mailboxes section of Users & Groups select your mailbox and click Details. Expand E-Mail Options, click Add, enter your new name for email address, choose domain (if you have more than one), click OK.