I actually had town guards turn on me when I helped kill off a master vampire in a town, I used my bow and I know I didn’t hit any friendlies in that battle, perhaps I was stealing the glory or something.
The only think I can think might have happened that would make some kind of sense is perhaps my follower hit one of the townsfolk or a guard.
Umm, Just now, I started my new character, and I went on the headsman's block, the executioner ready to kill me. Then, Alduin appeared out of the mountains, and didn't land on the tower...He just kept flying, and flying, in circles while the Headsman just stood there creepily watching me. I have no clue why this happened, and he never landed, so I had to start again.
SPOILER: I once did the quest "Waking Nightmare" with Erandur. When I was finished and destroyed the Skull, I walked back up the stairs. Then I walk over a dead Orc and I suddenly hear "Watch where you're going!" or something like that. It freaked me out so I started to look around for still living orcs, but none left. Hmm, creepy :P
On my recently started 'The Wizard' build (by RicardoGaming, or now he's called Modern Day Minstrel Productions ((on youtube, check him out))) I did the Camilla miniquest to get Sven as a follower. But when I said 'Follow Me' he said something like "Sure, i don't think master Neloth would mind, he'd probably like me to get out of his way".
I was coming back from a College quest, and as I entered the courtyard, the battle music for a dragon attack cued up(at this point a dragon had attacked me almost every single city, so I was getting pretty peeved). When it tried to land in the courtyard it glitched into the ground and and starting "breakdancing" as it was flying/bugging out in the courtyard ground. While I was standing there laughing, a good safe distance away, it suddenly teleported maybe... 30 meters forward, and killcam'd me.
The same thing continued to happen every time it reloaded the save. The dragon would attack, it would glitch into the floor, and then it would magically kill-cam me from impeccable distances. At one point it got me from the other side of the bridge. I eventually had to give up and revert to an older save, as I couldn't get to safety without it killing me.