logn (login-notifier) notifies you about logins of other users. It uses the file /var/log/wtmp for this task and scans this file for login of users. When someone logs in (e.g., using ssh, telnet or FTP) an informational line about the login is printed on your console. To ease idling around on a remote machine with firewall/NAT between you and the remote machine, logn outputs an ASCII NUL character every 8 minutes.
