Interested in WWI air combat? Have an old copy of CFSIII laying around?
Check out Over Flanders Fields:
Quite a little project, and still in development, but workable now. I just got the thing installed, and flew around a bit in an Albatross....Pretty cool. The CFSIII engine is not the best flight simulator around, but this seems pretty decent, and more to come. Installation is a bit complex, there's a big main file, and five updates that have to be installed in order. Still, I got the whole thing up and running in a day, using a "fresh" install of CFSIII. And yes, there is multiplayer as well as campaigns and missions.
CFSIII was what I was playing when I first heard about bf1942. I remember when the first drivable vehicles mod came out on some website (cfs3 outhouse?). I wish my cfsIII cd wasnt all scratched up...