The act of fouling up an internet forum by posing useless hypotheticals, drudging up dormant shitstorms and posting innumerable polls with no conceivable purpose, merely to see your name in lights.
eugene: "What the hell happened to this forum?! It's like half of you are are mm'ing."
mm: "Poll: do you think this forum has gone downhill since my increased presence here, or not? Or does it not matter in the least? In any case, please respond. Or not."
Slang for "making memories." Attending an event or performing an action with the conscious intent of creating a memory from said event or action.
"What are you guys doing?" "We're just MM'ing over at Roy's house with fingerpaints. You should come!"