[ Thanks to jmalasko for this link.
]
“Keystroke dynamics is a relatively new field that
enables identification of individuals through statistical analysis
of their typing patterns. Previously published articles on
developerWorks have shown how to integrate the concept of keystroke
dynamics into your applications, as well as a real-world example of
modifying Gnome Display Manager (GDM) to require a correct password
and a “correctly typed” password. This article presents tools and
code allowing you to move beyond a single application of keystroke
dynamics, and monitor your entire X Window System environment
continuously for characteristic patterns of the
typist.”