To not appear on this list, just set a password.

To actually be secure: Bind only to localhost, tunnel over SSH, OpenVPN, etc.

Minimally, require a password. This password would be separate from your Windows/Linux/OSX account password.

You could also use a non-standard port or configure some sort of port knocking system, or just close the VNC port to the outside world and allow connections over VPN or SSH tunnels only.

Is it running through an SSH tunnel? If not, its not remotely secure.

Switch to NX instead.

I usually make it available on localhost and use an SSH tunnel to access to it. Nothing fancy, but effective.

Do you at least require a password?