A bit late to this discussion (understatement I know), but running this type of private game server was partially what got me in this industry. In my case, I was running relatively successful Maplestory private servers back in 2008, on the order of 12,000~15,000 concurrent users.<p>Hundreds, probably thousands of these servers cropped up overnight after the first "core" was created, and many many variations of that core quickly followed. At some point, many of us in the private server community caught wind of Nexon (creators of Maplestory) going after certain kids for their private servers. This was an everyday occurrence. Almost always, it was in the form of a Cease and Desist letter.<p>Many of these servers had < 10~50 users concurrently and were run on home computers as many of us had non-existent budgets. Most servers were merely carbon copies of each other, as the owner would be able to create the server by using some reputable core and a setup guide. As with anything, a lot of traction was gained by servers that put development effort into adding their own touch into the game (alternative currencies like chickens, alternative bosses like Sonic the Hedgehog, and rebirth systems that let you utilize the skills of multiple character classes at once), and ones who were frequently engaging with their community and hosting in game events/contests.<p>There were private server rankings. Everyone would be vying for votes to get to the top 3 and gain visibility, which invariably resulted in them receiving letters. Those of us that became significantly more popular and had players actively going out and advertising for us quickly came under the spotlight and received letters with the threat of legal action if not promptly shutdown.<p>In fact, these shutdown letters were such a big part of the scene at the time, that some popular servers got shutdown by competitors sending fake Cease and Desist letters (don't ask how I know)...the response would typically be a quick and simple shutdown, waving goodbye to the community. Some owners with more skin in the game would deviously "shutdown" their server, then "re-birth" it as a different, smaller server since any communication sent in game was unlikely to be seen by Nexon. Few brave souls would post the Cease and Desist on their website while taunting and berating Nexon, though I never found out what happened to those guys.<p>Seeing this post brings back so many memories -- Honestly, a lot of time was wasted on that game but I would not be doing what I do today if it weren't for the people I met while doing it (my next major project was with a friend of a dedicated player on my server). It was also lots of fun.