Oh gods, I love Nationstates so much. So I'm probably somewhat biased on the matter. But here goes anyway.
Nationstates is, in essence, a browser game involving running a nation. Every day, you'll get a set number of issues to resolve, from freedom of speech laws to space research, and even a huge, branching, multi-issue chain dealing with turmoil in Brazilistan. And you're supposed to choose from the options you're given to shape how your nation develops. The best part of this, really, is the sheer absurdness some of the proposals, or issues for that matter, display. Banning anything from automobiles to the internet, deifying your leader, and processing dead people into snacks are absolutely things that you can do. So that's pretty fun. Not to mention, choosing an option might not necessarily bring the result you expected. Allowing flag burning apparently increased the tendency for flag-burning mobs of people to turn into straight-up burning mobs of people. It's best not to question the madness.
Besides issues, there's a couple more things as well to note. Nations are grouped into regions, which essentially serve a social function. Through the regional message boards, people can talk about whatever suits them. Plus, the fact that a region's WA Delegate (more on that in a bit) often has the power to change regional settings, including kicking people out of regions, a metagame of sorts has developed, where coordinated groups of raiders try to wrest control of a region's delegacy, mildly vandalise it, and then run off. So that's a thing, I guess.
Now, the WA. In short, 's a group of nations that pretty much anyone can join, and it functions as a rough analogue to our UN. Drafting resolutions on various things, and putting them to vote. I'm not overly active in that sector, so I'm afraid my explanation pretty much stops there.
Anyways, it's fun. I personally run a couple nations, mainly for the variety. And 'cause having a cartoonishly evil dictatorship brings me much amusement. Especially when I tattoo barcodes on my citisens and spike their drinking water with drugs to keep them under control.
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