An email address which is not permanent is called temporary email address. Temporary email address lasting only a short time.
List of website provide temporary email address:
5.10 Minute mail
1. Disposable email is a service that allows a registered user to receive email at a temporary address that expires after a certain time period elapses. Many online discussion forums, blogs and websites ask visitors to register before they can post comments, view premium content or download white papers. A disposable email account will allow the visitor to sign up and verify his registration without exposing his primary email account to spam.
2. A disposable email account, which has its own inbox, reply and forward functions, can be contrasted with a disposable email address, which is simply a service that forwards messages to a user's primary email account.
Email spoofing is the creation of email messages with a forged sender address. Spoofing is when a spammer sends out emails using your email address in the From: field. The idea is to make it seem like the message is from you – in order to trick people into opening it.