Logon Warning Banner

I've been asked many times for a logon banner, so here's my favorite:

WARNING!!!This system is solely for the use of authorized users for official purposes. Unauthorized access or use of this computer system may subject violators to criminal, civil, and/or administrative action. You have no expectation of privacy in its use and to ensure that the system is functioning properly, individuals using this computer system are subject to having all of their activities monitored and recorded by system personnel. Use of this system evidences an express consent to such monitoring and agreement that if such monitoring reveals evidence of possible abuse or criminal activity, system personnel may provide the results of such monitoring to appropriate officials.