I've updated the OP slightly to include a bit about sharing tabletop stories.
Here's some of mine:
While playing DnD 4e with my younger brothers. One of them wanted to be a changling (basically a race of shapeshifters) so I let him because that's pretty cool. Then when they were sneaking up to a hobgoblin encampment he rolled very welcome on an insight check and learned the name of some hobgoblin leader. He then decided to shapeshift into that leader and proceeded to infiltrate the camp while the rest of the party was busy fighting goblins. It was one my first time GMing but I ran with it and he ended up keeping the leader from discovering all of his soldiers were dead until it was too late.
A bad time I had was when I was in another 4e game with a GM that was a bit too much of a rule lawyer. My character was in a pit and had to roll to climb up 30 feet of rope. In the stated rules you have to make a strength check every 10 feet. Well I rolled a natural 20 on the first 10 and expected to just be up at the top because, y'know, it's a crit. No. He had me roll for each and I swear increased the DC each time for whatever reason. Boooo... So I ended up back in the pit and took way too much falling damage.
@artisanbreads: You should definitely check out the Campaign podcast then. It can be very silly but Edge of the Empire is an interesting system that works surprisingly well in podcast form.