I’m embarrassed that I’ve been here two years and still can’t figure out what “MPSIMS” stands for. Help . . . please?
. . . in conjunction with, for example “Mr. Blue Turtle, I MPSIMS You.” Is it still “Mundane Pointless Stuff I Must Share,” but with a specific person?
The mods have been trying to keep an appropriate level of vitriol in the Pit, and have developed a tendency to move threads that aren’t particularly Pit-worthy into MPSIMS. Therefore, if one wanted to post a minor complaint about someone (particularly in a jocular manner), one might just go ahead say “I MPSIMS you” and just put the OP in MPSIMS rather than saying “I Pit you” and then end up with the mods moving it to MPSIMS anyway.
How do you get to the Dope if you’ve never seen this page?
I think the mods should move this to … another forum but I can’t quite figure which one. 
How did you get to the reply button without seeing this post:
You mean it isn’t My Pet Snake Is Missing Something?
Hey. At least I’m resisting the temptation to hijack this into a discussion of CoCC. . . .
Incidentally, MPSIMS was a Straight Dope abbreviation before it became a forum. Indeed, it started on the Straight Dope message board on AOL before the SDMB moved to its own site (owned by the Chicago Reader). Somebody wanted to start a thread that wasn’t a factual question but simply a chance for everybody to discuss what’s been going on with their life, so they called the thread “Mundane Personal Stuff I Want to Discuss”. Eventually it was decided to create a separate forum for such questions.
Excuse me, “Must”, not “Want to”.
I think Hunter Hawk answered the question, but in case it isn’t clear, the verb to pit something or someone means to start a thread in the BBQ Pit forum vehemently complaining about them. Occasionally, such threads are even titled “I Pit (so-and-so).” To MPSIMS someone, then, would be the (humorous) mundane analog to this.
Not exactly. Someone started a thread called “Titanic Wallpaper”. The entire post consisted of a link to…Titanic (computer) wallpaper. (This was in 1998, iirc, when the movie Titanic was supa huge.) The next post to the thread was something to the effect of “You started a thread to link to Titanic wallpaper? That’s it? Why not just call it Mundane Pointless Stuff I Must Share, sheesh!” On AOL, you could change the title of the thread with each post, so the following poster retitled the thread and voila: a new Doper phenomenon was born. So MPSIMS was just a single thread, and any time the mundanity threatened to turn into an actual topic (ie, a mention of baking cookies might be followed by a request for the recipe, which might turn into a discussion of baked desserts), there would be calls for the participants to start their own thread and keep the topical discussion out of MPSIMS.
Huh! I’ve been around (more or less) since the switch from AOL, and I never new that part of the story. (Well, I didn’t know it five minutes ago. With my memory, I can’t swear I never knew it.) Are either of the two posters you mentioned still on the boards? If not, would I know them anyway?
Geez, my mind must be going. The thread from the AOL board was not titled “Mundane Personal Stuff I Want to Discuss”. It was titled “Mundane Personal Stuff I Must Share”. Kyla is undoubtedly right about the exact sequence of events (which happened back in 1998, I guess). All I can remember now is that I barely glanced at the thread at the time.
I tend to think of it as, “Mundane Pointless Shit I Must Share.”
I am such a potty-mouth.