One of the things I've been working with on and off the past few weeks was the implementation of GLFog in 3DGE.
In looking at other DOOM engines, I can see that most of the fog is generated in 3d slab space or by linedef triggers. That wasn't going to work, so I decided instead to create a sector special that fills with full real fog. The only downside is that as of now, dynamic light doesn't emit in a sector full of fog, so this will have to be worked on a bit. Fog is something that I always felt would enhanced Hyper's atmosphere and it definitely worked. While the fog in the screenshot is sort of a poison color, it can be modified in the script files according to what sector special you pick. Pretty awesome stuff. It feels more "real" and volumetric than other engines.
Just felt like sharing that with you all. Next, more Hyper-specific stuff.