Electronic Token (changing) Password

I am wondering if anyone has successfully added electronic token (like RSA SecurID) to control access to the router's SSH. As I understand it, a 12 character password should be used. If the password was persistently changing, a changing password thwarts a replay attack.

If you have successfully implemented, I'd love to hear more about the software used. In the interim, I found this interesting morsel:

http://sourceforge.net/p/stoken/wiki/Home/