One way we make that data available is as marks mapped onto scroll bars. One can readily see where edits were performed, who performed them, their age, and amount of time spent on them. Attribute-mapped scroll bars have the very nice property of collocating information display with navigation control points. For example, one can see who has read various parts of a document. This can be used to identify people who have recently consulted a manual page for a topic of interest.
Groups can filter mail based upon their members average time on message.
Source Code Wear. This provides an extensive programmable interaction history mechanism that captures time-stamped actions and current context. Our prototypes modify document-processing as we usually think about it in two significant ways. First and most importantly, they move reading and editing from the realm of private to semi-public activity. If this were to occur on a large scale, it would represent a significant cultural shift.