I don't know if it's still around that much any more, but the old "Squad Leader" tabletop game fan community. Hole-Lee-Sheeeit. These guys do major WW-2 battles right down the individual squads that took part. Hell, for some of the small unit actions, I've seen guys use the individual people who took part in those smaller battles.
Battle-Tech geeks are just as bad. Man, one of the gaming shops I went to had several tables devoted to those guys. Whoo-Eee. I could give you sperg tales for days on whether or not Clan heat sinks should be allowed for Inner Sphere merc groups after the Battle For Terra unless that merc group had salvage contracts for a particular battlefield, that can only be supported by canon.
Which may be half a sentence in one of Stackpole's novels.
The only people worse than those guys were the Model Train spergs.
You've never seen a sperg sperg till you've seen a model train sperg sperg. You think those guys who buy $11K worth the DLC for Train Simulator 2016 are bad? I worked at a model store, and IRL model train guys have returned models of engines because the wrong number of rivets were on the steam engine. Because the amount of bolts on the boxcar was wrong. I've seen a guy come in and drop $5K on a bunch of models. The shop I worked out delivered, because some of these guys never leave their houses and make fucking bank off the VB programs they make for other train spergs to control the big ass train layouts. One of the places I visited to deliver two vans worth the stuff, all the interior walls except for I guess like 1 or two rooms, were cut away, with just the load bearing beams remaining.
The entire rest of the house was dedicated to a scale model layout, including small mining towns, villages, log camps, stuff like this. This guy had actual small figures from Germany that he'd order through the shop.
According to my boss, who'd been in the business of model trains since I was a kid, that dude's house wasn't even that bad.
Train spergs, Battle Tech geeks, and Squad Leader spergs. The like of which you cannot find even on the worst sperg forums.