A few weeks back I picked up a real vt100 in a slightly grotty state, but cleaned up something terrific.
In my first year of uni I used one to log into one of the mainframes - probably in my first Pascal unit, but I could be mistaken there - even at the time they were on their last legs.
Dating from 1978, I give you the origin of the 'vt100 emulation' in so many terminals, a real live (and working!) vt100 terminal, connected to my current iMac via an (almost vintage itself!) Keyspan USB->Mac Serial connector, and a custom wired cable.
VT100 on IRC
I swore I posted this back when I first got the thing working, but looks like I was distracted. Since I took the pics the PSU keeled over, but looks like one of the main power transistors is the issue there - and they're still very available