Guerrilla Mail - Guerrilla Mail is a web-based app that provides a disposable and anonymous email address. Users of the service are not required to set up an account in order to send or receive emails.

MailDrop - maildrop is a Mail delivery agent used by the Courier Mail Server. The maildrop MDA also includes filtering functionality. maildrop receives mail via stdin and delivers in both Maildir and mbox formats.

Firefox Relay - Keep your email safe from hackers & trackers...

Mailinator - Any Inbox. Any Time.

Spamgourmet - spamgourmet provides email addresses that get created automatically the first time they are used, forward messages, and then automatically expire.

YOPmail - YOPmail is an interesting anonymous mail program that allows users to communicate with each other without compromising their original email addresses. Read more about YOPmail.