First time I went to Winterhold around level 25-30 (level 50 now) we (the town) were attacked by an Elder Dragon (the first one I had ever seen) that was thoroughly upset about the new fancy daedric arrow thrusted in his side. After he was upset enough about his new limb, he was definitely angry about the thundering blue that just dragged him into the side of a mountain. Pissed off by now, he turned tail and came barreling into Winterhold, divebombing into an unfortunate group of guards and throwing them from the cliffs edge, after landing on the opening gates of the college, me, my follower, and a few guards promptly (and in retrospect, idioticaly) charged in and found ourselves in the middle of a bridge with no railings and a nasty winterfresh stream of frost draining all of my, and guards, stamina and around half my health. I realized there was no way of retaliating so I became ethereal and leaped off the doomed bridge.
Might not have been the most heroic battle but was the most unexpected one i had.
Just when i thought Frost Dragons were hard enough.....