at one point we were hosted for free by a company called (IIRC) ThePoint.net. The one caveat of having free hosting was that we had to cap the player count that could be logged in to (again, IIRC) 100. I believe this was because the powers that be (were?) wanted to make certain that paying customers who were also using that box didn't experience any issues that might be caused by too many resources being consumed.

This doesn't really answer any of the questions or have a lot of specific relevance but it is an old piece of history that was tangentially related, so there.