Thank you Quintillus. Detailed well constructed answers make life so much easier.
It's a shame that with all the potential manpower on this site that we can't crowd-source an independent game. Ideally just patching together chunks code with simple Boolean logic gates to make it user friendly and universally compatible. It would essentially be a strategy game designer with no copyright protection. I wouldn't be able to offer much beyond ideas and game testing anyway.
Sorry, if you gave me the universe i'd ask if you had it in blue.
Didn't see your response when posting the above, just Delta Strife's... still getting used to the new Alert system. I'm glad the detailed answers are useful; sometimes I wonder if they're too much information at once, but I generally prefer too much to too little detail myself.
There have been several attempts at an independent game over the years. Most have been by individuals; there has been at least one effort to organize a larger effort, although timing is difficult with that since everyone's life circumstances are at different places. Steph made some interesting progress with his expanded editor that allows additional eras, and also was looking into his own game at one point, before switching more into modding other games. JimmyH I think it was also was making some progress at one point, but hasn't been on the site much lately; I suspect real life has kept him occupied.
The most successful progress of this type I've seen on CFC is actually ongoing currently, in the Civ1 forum. That is
this project, to create an open-source version of Civ1 that's fully compatible with the original game (and eventually expandable via mods). Although SWY took about a year off, he came back this summer and that project has now progressed, both from a gameplay and completion standpoint, beyond any other one I've seen on CFC. While it may not be Civ3, I think it is an exciting project, and in some ways a paragon of what could be done.
There's also
FreeCiv, which was originally based on Civ2, and has been slowly evolving over the years (being playable for quite awhile). The playable-in-browser version currently gets top billing, but the
traditional downloadable version is still available. Although I've yet to get into it like Civ3 or Civ4, in terms of a functioning, open-source Civ-like game that can be added to, it's probably the best bet currently.
Finally, there's the
Apolyton Call to Power II Project. It's interesting because the Call to Power II developers, Activision, gave the Apolyton community (or at least, some of the members there) the source code so they could continue to enhance the game. That's essentially the holy grail of what the CivIII community would like to happen, but Firaxis/2K are not currently willing to do so. You do need to have a functioning version of Call to Power II to play the expanded version, but you can buy that fairly inexpensively (and digitally) at
GOG. This is something I plan to try in the next year, but it's worth noting that there hasn't been an update in 5 years (the project started 13 years ago), so the chances of further releases is likely slim.
At this point I think the most likely seed for an effort like this would be a prototype that was at least somewhat playable, and made open source. And unless you could find someone who had as much free time and interest in Civ3 as I did 6-8 years ago, and as many skills as I do now, you'd need to have a couple additional programmers jump on at that point. Once that ball got rolling, I think it wouldn't be too difficult to get other people jumping on similar to what's happening with CivOne.
However, it may also be that at this point in time, the Civ3 and Civ4 communities would need to combine efforts to make a community game of comparable depth and breadth. The Civ4 community has a lot of talented modders - it allows more complex mods than Civ3, although it's not as easy to create moderately-complex mods - and I know they're also running into limitations of the game engine, although of a different nature than for Civ3 (in Civ4 you really can add new elements, with enough programming knowledge, but you run into issues like running out of memory more often than in Civ3, where it's really a non-issue). I'm assuming for now that the Civ5 community would be more interested in modding Civ6, as from what I've read so far it seems like primarily a successor to Civ5 (although with some interesting new ideas of its own, and a few elements rekindled from Civ3/Civ4). With the community size of 2007, the Civ3 community would've had a better chance of striking out on its own, but alas, the right project didn't come along at that time.
There are still discussions going on about both the possibility of a new, similar game, and ways to improve Civ3 despite its current confines, though. The amount of discussion ebbs and flows, and no one knows what it will lead to yet, but there still are some of us who think an interesting project, while perhaps not likely, is at least still possible.
As for myself, I don't have the time to try to jump-start a project myself currently unless I give up more of my other pursuits than I'm willing to, and even supposing financial concerns were not an issue, I probably wouldn't be willing to trade my current day job (which I enjoy, particularly the people I work with) for working with a remote team on a project, as I've found through experience that I work better with other people in an office than remotely (at least for what I spend most of my time on). But I do still have some ideas stacked up for ways I think Civ3 can be enhanced as it stands currently, and I could see at least a couple of those happening someday. Entirely new gameplay elements aren't possible (well... I do have a rough plan for one, but that's another story), but there I don't think we've completely exhausted what Civ3 has to offer yet.