You know what would be useful? A tree showing all the objects, their variables, procs, and descriptions of what they do, as defined by BYOND. This could go on some website. It would be handy to show to newbies. The reference has most of this information, but it would be nice to have it represented more graphically.
When do you want it by? :P
Maybe it would be even better if the BYOND object tree would have a checkbox to include individual declarations for BYOND variables (like density/opactity) and procedures so you can jump to them in the code...
In response to Exadv1
I think Garthor was talking about the documentation.

I do agree with the idea, though -- but I think it would be better handled with a double-click on the same object type. For example, if I double-click /obj currently, it takes me to the first /obj it finds alphabetically in my project. It would be nice if a second double-click on /obj would take me to the next /obj found, and so on. This would be easier than some sort of checkbox.