As a GM of my group I had a very funny episode... Well, several, to be honest.
The players was about to enter an apartment in the Barrens, where their objective was taken hostage.. Well, they knocked down the door, threw in some flashbangs. Before the flashbangs goes boom, in charges the ork, whom is played by a very nice fellow, but a wee bit slow on the uptake.. And THEN the flashbangs went off. his character was stunned into the next week.
The player looked sort of goofy, when the military guys in my group told him about the use of flashbangs. What I thought was common knowledge, wasn't. He thought they just went flash and no bang... The rest of the group thought it was hilarious and ever since, if he gets a wee bit uppity, we remind him of the flashBANG incident. Very very funny.
Since then his character changed his name into Flashbang.
Or when I was a player and I had this character named Morgue. Fomorian female from the SAS. She had a twin brother, who really wanted her married to continue the family name. To him the runs was a means to an end. For Morgue they were life it self. Brother dearest had finally browbeated her sister into accepting his choice of husband. My gods, the roleplaying was intense and sooo much fun!! It was best roleplay ever.
They were supposed to meet in a church and start from there. Morgue sort of had a volatile temper, so did her brother. Scotsman, redhead and highlander, not to mention a stickler when it came to honor and what she percieved as an insult. The screaming arguments we had at the top of our lungs during a run, or after or the fights.
She goes to the church and then engage in combat on hallowed ground because some outclansmen thought it would be a good idea to rid the world of her brother and her. Suitor engages in combat and at the end, all she says as she looks at him: You have merely won the right to woo me... I choose whether or not you are worthy of being my husband.
My fellow player/brother dunked his head into the table. Several times, then into the wall... Ohh, it was soo much fun.