Cryptgeon - Securely share self-destructing notes
Mailinator - Any Inbox. Any Time.
BURN.link - Send secure, encrypted, self-destructing messages
TempMail.altmails - Disposable temporary email addresses
1ty.me - If you need to send a password or some other form of simple but sensitive information to someone...
Harakirimail - Harakirimail is a free disposable email service. Just send email to anythingyouwant@harakirimail.