My most memorable moment Dm wise was when I had a level five wizard talk down a Tarasque. ( I very quikly figured out why both Pizo and Wizards of The Coast both make it impossible to talk to.) but as a player my most memorable moment has been massaging a alter-planer Black Dragon bent on making everyone undead for his "deity" the stealthy character who was going to pour a poly morph potion on to sheep that the dragon had summoned to eat rolled a one and made the most noise any man possibly could so the dm said everyone else roll a dex, i rolled a 20 and moved from massaging/ polishing his scales on his side with healing oil to massaging his face with the oil saving our Mage,Ninja,hard hitter. (also i play fighters who are usually LW aligned. So what are your most memorable moments.
So. Once my DM relied way too much on rolls. We had to roll for EVERYTHING. So, I found this crazy cool sword. I had to roll to pick it up. I rolled a one. I tripped, knocked the sword upright, and impaled myself on it.
For April Fools I brought out a different set of character sheets and ran a generic action trope session of Fightsword 80M, that was totally not a Warhammer 40k clone I made up. When the players reached the BBEG. Me: *Cutscene* The Bad Guy begins his monologue about how you upsetting his plans will be dealt with by his pet cat Mr. Fluffykins. *blahblahblahblah* Prepare for death. Player: Um, I shoot him. Me: What? During his monologue? Player: Yeah. There's nothing stopping me from doing it right? Me: Roll your attack. *hits* Damage... You just sniped dead him mid-sentence. <Other players in shock> Player 2: But you said it was a cutscene! Me: I didn't say you couldn't do anything. Player 3: What was the thing about a cat? Me: Oh yeah, the small house cat thing in the middle of the room just became the size of a rancor.