Trev:
Some staff at MS use slickedit

The feature I like is the API pluggin auto detect structs and list available functions/commands.
Fanscale:
With TextConverter/Parser one could convert from one programming language to another. EG C/Basic conversion
Or from one API to another !
For example a program/game written using DirectX could be converted to SDL/OpenGL.
Windows GUI eg a Visual basic 'form' could be converted to Blitz/E/C source code etc
I also use Visual Studio, but I hate to program for Amiga if I had to keep switching screens. I would like if VS could communicate with Winuea so I can debug/run Amiga app on the fly.