I've been on Carousel of Progress when it broke and stuck watching the same scene multiple times (like 4 I think?) before they finally let us exit.
But for true evac, I've been evacuated off of the PeopleMover. We stopped right below the astronauts right where Space Mountain trains go up the incline on either side of you. And there we sat for like half an hour. Did you know the astronauts move from the vibrations of the Space Mountain trains going by? Neither did I until we had plenty of time to watch it. About halfway through the wait time, they turned on the emergency side lights. It was hard to hear announcements where we were but eventually someone came and manually opened the doors to each car and led us single file out and along the track to a set of stairs right by the back trail between Tomorrowland and then Toon Town. The CM told us "do NOT step on the plastic center" several times but someone dumb blond in front of us did just that and cracked it.
It was definitely a unique experience!