I've just spent the last bit of my work day reading these stories. As a newer player(and even newer DM)I don't have any stories of my own yet.
But this newest group I'm DMing has 1 player with experience of over 15 years, 2 players with 2 years experience, and 2 players who have never played before.
Hopefully, I'll have some stories to contribute soon :)
Edit:
I do have a story. From MY first ever campaign. I was playing a Dwarven Cleric of Sarenrae.  We were exploring an old asylum, Mezzik heard footsteps downstairs, and upon seeing a group of undead downstairs, I proceeded to throw a fireball down there. 
I didn't care to realize that all the walls were wooden, the stairs were wooden. Oh, and if we would have looked in the basement, there were barrels of highly flammable fluids.
Needless to say, I burned the whole asylum down that night. Killing a few innocent patients. And burning all the clues we were supposed to find.  ...oops.
Darn Fireballs!