I could (literally) write a book of funny gaming stories. I'll try a few here:
DM: "This is the Keeper of the Book of the Dead. In order to pass into the realm of Orcus, you must convince the Keeper that you are of the nature of the dead."
Me (playing two halflings): "My sorcerer says: I am the undead! Feel my horrific aura of fear!" (rolls intimidate)
DM: "The Keeper consults his books, shrugs, and gestures for you to pass. What does (your second character) do?"
Me (jerks thumb to the side) "Oh, I'm with her."
DM: "Roll bluff."
Me: "53."
DM: "Um."
Me: "I totally just made that roll, didn't I?"
DM: "Yes."
In one of the first games I played with a real group, we were tasked by a local church with transporting some kind of magical rug/tapestry for study. The first night out, we made camp in a forest clearing. Around midnight, we were attacked by 10 skeletons with shortswords. We fought them off, picked up camp, moved about 50', and went back to sleep. In the morning, we set off.
The following night, we made camp. Around midnight, we were attacked. By 10 skeletons. With short swords. We fought them off, picked up camp etc. etc. etc. The DM said "these skeletons seem a bit battered and damaged."
This same sequence repeated for the next 5 nights. On the sixth night, when we were almost to our goal a necromancer showed up with 2 shadows and kicked the crap out of us, partly because we hadn't had a decent night's sleep in a week. When the adventure was over, one of us asked the DM, what the hell was the deal with those skeletons. He said: "You guys never did anything with the bones after you whacked them enough that they fell over, so when you left in the morning the necromancer raised them again and sent them after you. He wasn't going to risk his own life when he could just keep spamming you with the same ten skeletons until you wore down."
1. Party confronted with two rickety platforms dangling near a slippery ledge circumventing a chasm.
2. Party consults balance scores. Balance scores are found to be lacking. Extremely.
3. Elaborate plan emerges involving at least 5 ropes, pitons, and swinging on the platforms in order to cross the chasm.
4. During step 4 of this plan, in which the entire party is clinging desperately to a wildly swinging platform, we swing straight up into the grell that was hiding in the shadows the entire time.
5. The DM, at this point, decides to illuminate the grell's state of mind for us: "It's my birthday!"
My group can be pretty well depended upon to either a.) take no precautions of any kind whatsoever or b.) take absolutely ridiculously elaborate and completely misplaced precautions that wind up producing more danger than existed before they were taken. Also, any time the DM in our group says "roll X" meaning "This is an incredibly stupid plan with no chance of working but I'm going to let you roll anyway because I don't feel like arguing", that's the time when the person who's invested a ton of skill points and a stack of magic items in that skill, buffing it to absurd proportions, will proceed to roll a 20 and get some result like "you can sell clearly yellow snow to the tormented souls in the frozen depths of Cania" or "You jump so high you exceed orbital velocity".