For ATMs, the idea is out there, but it has never been implemented. Snopes on this:
The Credit Card Accountability Responsibility and Disclosure Act of 2009 compelled the Federal Trade Commission to provide an analysis of any technology, either then currently available or under development, which would allow a distressed ATM user to send an electronic alert to a law enforcement agency. The following statements were made in the FTC's April 2010 report in response to that requirement:
FTC staff learned that emergency-PIN technologies have never been deployed at any ATMs.
The respondent banks reported that none of their ATMs currently have installed, or have ever had installed, an emergency-PIN system of any sort. The ATM manufacturer Diebold confirms that, to its knowledge, no ATMs have or have had an emergency-PIN system.
It's an interesting idea, to fight the standard social engineering attempts by hiding the password from the user. In a sense, all the conscious mind gets is "********". The paper is called "Neuroscience Meets Cryptography: Designing Crypto Primitives Secure Against Rubber Hose Attacks". Here is a popular write-up and the paper PDF.
Abstract:
Cryptographic systems often rely on the secrecy of cryptographic keys given to users. Many schemes, however, cannot resist coercion attacks where the user is forcibly asked by an attacker to reveal the key. These attacks, known as rubber hose cryptanalysis, are often the easiest way to defeat cryptography. We present a defense against coercion attacks using the concept of implicit learning from cognitive psychology. Implicit learning refers to learning of patterns without any conscious knowledge of the learned pattern. We use a carefully crafted computer game to plant a secret password in the participant’s brain without the participant having any conscious knowledge of the trained password. While the planted secret can be used for authentication, the participant cannot be coerced into revealing it since he or she has no conscious knowledge of it. We performed a number of user studies using Amazon’s Mechanical Turk to verify that participants can successfully re-authenticate over time and that they are unable to reconstruct or even recognize short fragments of the planted secret.
While this approach does nothing against man-in-the-middle attacks, it can probably be evolved into a unique digital signature some day. Cheaper than a retinal scan or a fingerprint, and does not require client-side hardware.