Dead address temporary email account.

when used for registering at boards. Plan to be banned for using such emails.
As most don't know, we as owners get bounce back emails when these type of trash mail email addresses are used.
easier solution is not to receive any emails from the board

@deadaddress.com added to the ban list

The thing you may or may not realize is that say you do join under one of these addresses. and you posts. Each time someone posts in your thread, An email can be sent to that address to let you know someone possibly answered your question . (of course boards can be set up differently as a default)
When it doesn't make it to your email, it sends a default email to the owner (webmaster email account) notifying them that the email bounced.

This clogs up the admin account with trash and can become a pain as others may have a real problem and the admin has to wade through the crap trying to get to the people that really need help.

Plus, who knows.. there might be an announcement that may directly effect you and you don't get it because of some trash email that you used ..