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.
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.
Firefox Relay - Keep your email safe from hackers & trackers...
10 Minute Mail - Temporary disposable e-mail service to beat spam. Avoid spam with a free secure e-mail address.
Mailinator - Any Inbox. Any Time.
Inboxes.com - Inboxes - disposable temp email, protect your inbox from spam.