My entire purpose to post in this thread was to utter those words if no one else beat me to it

Cthulhu is fantastic fun and you can bet that if you are playing a one shot, most likely only 1 person will be left alive at the end. They will, sadly, probably be crazy, but that can't be helped

I have a couple of other things tho.
One of my early groups was playing 2E D&D and we ended up in the bad guy's lair. Evil priest has been sending his goons at us and we finally catch up to him. We're only somewhere in that 1st-3rd level range, so not super high powered or anything. We manage to kill the priest and someone asks what we should do now. Someone suggests we pitch the priest up on his own altar and does so while several of us scream "NO!!"
Next thing you know, crack of thunder and an avatar of his god appears and he's rather pissed off at us killing off one of his prime clerics. He raises the cleric on the spot and then they both disappear with an appropriately menacing warning. This led to the common phrase for our group of "Never throw the dead priest on the altar"
Same group, first session we ever played. One of the guys had just been playing occasionally in the cafeteria at school w/a friend of mine and I think it had been 1E. 2E had just come out and we were putting together a new group and we all made characters, got together for the afternoon and sat down. We started going around the group asking everyone to describe their character. We got to my friend Brian and he said "I'm a six foot elf!" and that was it. Needless to say, we busted out laughing and still poke him about that to this day
One time in the early days of 3E (wow, feels like I should be yelling at kids to get off my lawn or something) I was helping a friend playtest an adventure. We were about 8th level I think and he had made a dwarven cleric/fighter for me. I can't remember if he was more cleric or fighter, but I took to the concept that he was a very devout warrior. Kneeling in prayer w/his axe by his side, that whole thing.
Well we were on these massive ships, something stupid like several miles high, and we were attacked by these huge insect things. A couple of them break thru the wall of my room and start trying to kill me. I kill one and the next one I roll a 1. Now he had given me a magic axe. This axe was passed down thru my family, it was a part of me, I don't think I had a non-magical spare handy. So I roll that 1. He then has me roll on a table and we find it flies out of my hand in a random direction. One more die. Oh yeah, thru the hole in the side of the ship. I scream "NOOO!!!!" and dive out after it. It was completely suicidal, but also what I really felt my guy would do. No, he was not Chaotic Stupid
Since I am quite effectively out of combat and I will be falling for a LONG time, he goes on to someone else's turn while I try and figure out if I can save myself. I dig thru the DMG looking up falling damage and look at my spells. I cast some spells on myself as I was falling...something like Resist Energy (Water) for less damage from hitting the water and Bear's Endurance for the bonus health. I think between the 2 spells I managed to boost my health high enough that even w/the max falling damage I still lived with about a dozen health.