Well, I have, though fortunately there was a happy ending in that case:
I'm a member of the forum that will be the focus of this story (SpaceBattles, hereafter referred to as SB). Around the time that I joined in December 2013, the site had been experiencing server issues for some time by that point. The server hardware was getting quite old (IIRC, something like a decade old by that point) and was beginning to be overwhelmed dealing with the sheer number of posts and their associated content by that point, to the point that things were getting rather laggy (with periods where the forum would become inaccessible altogether). To make matters worse, the then-owner of the server was unable to be contacted by the rest of the administration staff, which meant that the problem would be out of their control for the foreseeable future.
The problem (predictably) only got worse in early 2014, to the point that members started calling this period "Lagmageddon". The increasingly dire connection issues (among several other concurrent issues) led a number of members to migrate to a previously-created spinoff forum called Sufficient Velocity{1.} (or SV for short).
{1.} Named for an in-joke on SB's Vs. Debates subforum: A joke answer to the question of "How many of X would it take to defeat Y?" is "One, at sufficient velocity", owing to the fact that any object traveling extremely fast will thus have a lot of energy to it, and if you knew the mass of X and how much energy was needed to defeat Y, then you could calculate the minimum velocity that X would need to travel at in order to defeat Y.
Fortunately, a much-welcomed change came in the nick of time. New owners bought the old server and replaced it with much more modern hardware (which has since seen more rounds of refurbishment to keep things from ever becoming so dire again). The site not only still continues to this day, but has actually seen notable growth in the number of users in recent years!
