Q: What is this "NS Summer" I keep hearing about?
A: Aside from being a meme spun off from Game of Thrones, "NS Summer" and variations such as "Summer already?" and "Sure is summer in here" is a relatively recent term for a phenomenon that the mod team has been aware of since 2003, but really caught the general playerbase's attention around 2012 when the effect was particularly pronounced and enhanced due to the US presidential election that year. It's been known by other names prior to that, mostly along the lines of the "summer nazi invasion."
Basically, during the summer months in the northern hemisphere, most school age children and teens in North America and Europe (the lion's share of our users come from these regions) are on summer break from school. So you get a large number of bored and/or inadequately-supervised kids with too much free time looking to stir up trouble and get attention that find their way to the site to troll, flame, spam, and generally make a nuisance of themselves. One of the easiest ways to do this on the internet of course, is to drop some Nazi-flavored rhetoric, which lead to the perception prior to 2012 of a summertime invasion of nazi trolls. Generic nonsense spam and porn spam are also not unusual, but the wannabe Nazis do tend to stick out more for some reason.
The "NS Summer" period runs from roughly mid-May to the beginning of September, and during that span of time the mods see a marked increase in rulebreaking behavior (in especially bad years, roughly 50% or more compared to the non-summer months.) Most of this tends to come from very new nations rather than more experienced players, and they tend to have very short lifespans, whether due to getting deleted or from being abandoned because the owners got bored. Typically the tail end of August is when it really peaks, as you've got younger students running out of summer break, and returning or new university students going to the dorms and going a little crazy for whatever reasons.
There's a similar spike at the end of December into early January, mirroring the general vicinity of schools taking winter break, but the winter spike is both shorter in duration and much less noticeable in intensity than the summer months. My best guess as to why is that 1) winter break is usually shorter than summer break, and 2) people are busy with the winter holidays and too preoccupied with friends/family/parties and such to have as much free time for troublemaking.
Q: I see it all the goddamn time, but what exactly is "DEAT?"
A: As most folks can probably infer from how the term gets used, it's a piece of slang for "deletion." It can function as a noun or a verb ("I got 10 DEATs on that spammer's puppets!" or "Somebody wanna go DEAT that guy?" for examples.) It's also an extremely old piece of slang, the expression's origins going back to 2003 and the first batch or so of NS mods. If my memory serves correctly, since-retired game mod Neutered Sputniks brought the term over to Nationstates from another site he had been part of, and explained its origin as a typo someone there made when caps-yelling "DEAD!" The expression caught on here, likely due to "DEAT" functioning nicely for both "dead" or "delete" and remains one of the most common expressions for deleting an account today.
Q: Hey Reppy, that thing in your moderator sig, the Kiri-whatywhatbit, the hell is that about?
A: "Kiritateru Teikoku" is better known as the "Sword of DEAT." (The linked image contains both the original 2003 version of the design, and the more recent 2009 revision.) The "reason" many players started to refer to it as the Sword of DEAT instead of the name was that it was supposedly blasphemous to refer to the fictional blade by its true name. I personally suspect that the real reason is nobody wants to be arsed remembering how to spell the bloody thing properly. Hell, I rarely remember the spelling, I just copy and paste the thing when I paste my mod sig into a post!
And for those who are curious "Kiritateru Teikoku" is supposed to mean something to the effect of "Slayer of Nations", though I am quite certain my anime-nerd-and-internet-dictionary Japanese has it at least mildly botched.
And for a fun fact: I actually built the 2003 version as a wooden prop; in real life, the blade is about six feet tall from tip to pommel... which, coincidentally, is taller than I am by a decent margin. 
So... floor's open! Any random tidbits you've always wondered about, but were too afraid to ask/didn't know where to post it?
~Evil Forum Empress Rep Prod the Ninja Mod
~She who wields the Banhammer; master of the mighty moderation no-dachi Kiritateru Teikoku
