Endlessh - SSH tarpit that very slowly sends an endless, random SSH banner.
SeKey - Use Touch ID / Secure Enclave for SSH Authentication.
BLESS - SSH Certificate Authority that runs as an AWS Lambda function and is used to sign SSH public keys.
sslh - Applicative Protocol Multiplexer (e.g. share SSH and HTTPS on the same port).
Eternal Terminal - Re-Connectable secure remote shell.
WebSSH - Web based ssh client.