Halo Ringworld: DONE
10/8/2012: Welcome Kotaku and Reddit visitors! While you can get a good look at the landscape details from the above picture, this is not the completed, assembled Ringworld--just the four sections of the inner ring. You can find better photos here:
If I can figure out a way to properly display it within the next few weeks, this will be at BrickCon 2012.
I will also be entering it in the Design a Lego Halo Set contest, provided the admins don't take one look at this and go "uh, this is not what we had in mind". ;)
These are the inner ring (landscape) segments, which have been my stumbling block for quite a long time. The outer ring (hull) is not pictured here, but you can see it in the WIP set. I might need to adjust the length of the inner ring by a little bit one way or the other once I try fitting it into the outer ring, but that's why I left myself open stretches of ocean and ice that I could expand or contract as needed.
Now to figure out how to set it up and photograph it...