The US military is developing a new identity verification system that could replace passwords and biometric systems for web users.
The technology is being created under a multimillion-dollar contract for researchers at West Point, home of the army's military academy.
The focus of West Point's work is on "cognitive fingerprints" rather than physical characteristics such as palms, face, DNA or iris recognition.
The biometric application programme interface (API) is based on the emerging field of behavioural-based biometrics, where algorithms are used to confirm identity by recognising the way a person uses desktop or mobile device.
It may include observing the rhythm of writing, how a mouse or cursor is moved, frequent typographical errors and typing speed.
It is a major step forward from existing identity checks and is described in a contract document seen by Sky News.
"Just as when you touch something with your finger you leave behind a fingerprint, when you interact with technology you do so in a pattern based on how your mind processes information, leaving behind a 'cognitive fingerprint'," the document explains.
"The biometrics program is creating a next generation biometric capability built from multiple stylometric/behavioural modalities using standard Department of Defence computer hardware."
Stylometrics includes the analysis of how text is constructed, with existing technology used for checking for academic authorship and plagiarism.
The military expects to develop the system for encrypted data communications across all of its services, as part of the Defence Advanced Research Projects Agency active authentication programme.
With eventual transfer to the civilian world, it is expected to be used for personal verification in online banking, shopping and control of numerous future home devices as part of the "internet of things".
West Point has become a key hub for the US military in developing the system, which is now in its fourth phase.
IBG was bought by Novetta Solutions in 2012, which described its capabilities as "biometrics and virtual identity management".
At the time Novetta boss Peter LaMontagne described the company's work as spanning "the full spectrum of cutting edge technical challenges, from big data and cyber security to social media and gaming, all in a national security context".
Tech strategy consultant Sharif Sakr from ViaTheWire told Sky News: "We're living in the Wild West era of the internet and anybody can get away with fraud, harassment and spying on an industrial scale because there is no effective way to identify people online.
"For this reason, any tech that passively and rapidly identifies internet users could be an essential step towards making the web a more civilised place."
But privacy campaigners are expected to oppose the concept of invisible and seamless identification, as it may allow for wider monitoring of society.