Been stuck plenty of times, but some of my faves were:
Getting stuck at the end of ToT .. We were turned slightly toward the door to exit, and the lights came up, so I got to see some backstage I hadn't seen before. The guy next to me pulled out a book and read for the nearly 10 minutes we sat there.
On Dinosaur, 2 weeks after it opened, we got stuck, pointing slightly downward, at the end, right before the carnotaur's head pops out at you. We sat there for almost 20 minutes, and my husband busts out with, "And Bubba died, right there by that river!" That started a plethora of great lines while we sat waiting. Eventually, the carn's head popped out, and we continued on our way.
On TT, the car stopped on the loop outside. We were sitting at the angle for quite some time, when finally 4 CMs came out and pushed us back into the station. I felt bad for them .. those cars, esp. when full of people, must weigh a ton!