OpenSSH (http://openssh.org/ http://openssh.org/) grew out of OpenBSD, and that's used pretty widely (http://www.openssh.com/users.html http://www.openssh.com/u

OpenSSH (http://openssh.org/ http://openssh.org/) grew out of OpenBSD, and that's used pretty widely (http://www.openssh.com/users.html http://www.openssh.com/users.html).