1. A document management system, the system comprising: a physical-document monitoring device comprising: a document coupling device, a sensor coupled to the document coupling device, the sensor operable to sense a state of a document and to generate a signal representative thereof, and a computer coupled to the sensor and the document coupling device, the computer operable to determine a document state based on the signal.
6. The system of claim 1 , wherein the document state comprises an environmental condition of the document.