me too
I did the same sort of thing (emulating a login prompt from one of a set of guest accounts to see who would could enter their credentials), although in this case it was a Novell NetWare system. The not-too-bright CS teacher at the high school typed in her admin account, and that gave me a chance to explore the Novell admin tools. Eventually, one of my fellow students ratted on me, and the whole thing got me kicked out of the CS course, banned from the credentials that helped entrance into university, and very nearly kicked out of the school.