I mused before in the Sick posting which you can read about here. hard cover published in '95, called Fatal defect, chasing killer computer bugs, by Ivars Peterson. When a major incident has occurred, I have often longed back to viewing the LCD panel on a network device, not only to identify an issue but more importantly to eliminate one. The LCD panel is also a great visualization during diagnostics. I was impressed that Juniper Networks has incorporated a LCD panel in their range of switches! Switches have finally returned to being sick again!
* Another vendor to do this is Mikrotik!