So, my list:
Many/most of the programs are WIP, but should work, unless otherwise stated:
Tools for making meshes & textures:
FOMM: Fallout Mod Manager: Used to unpack Skyrim BSA files (other programs can do the same)
Blender/3dStudioMax: Used to make/edit meshes, animations etc.
Blender-Nif plugin: Used to open nif files directly in Blender. WIP, not fully functional yet
3DstudioMax-Nif plugin: Used to open nif files directly in 3DstudioMax. WIP, not functional yet
NifSkope: View/edit nif files. WIP – needs Throttlekitties modified nif.xml
Photoshop/paintshop/GIMP/Whatever: Used to make/edit textures
It’s possible to make new statics and weapons by saving meshes in Blender/3DstudioMax as obj, then opening the mesh in NifSkope, add texture here and save as nif.
Tools for making Skyrim mods:
TESsnip: View/edit ESP and ESM files. Used for making gameplay and mesh replacement mods without the CK, using hexeditor
The CK: Used for just about everything, hopefully
Script Dragon: Engine extender. Used to make powerful scripts without CK
SKSE: Script Extender. Used to make powerful scripts not possible with CKs basic script language
Tools for use in installing mods:
Nexus Mod Manager: Download and install functionality
BOSS: Basic mod sorting to avoid conflicting mods
Wrye Bash - Skyrim: Safe uninstalling of mods (so far)
File formats:
BSA: Achieve format used to hold all Skyrim ressources, incl. Meshes, textures, scripts
NIF: NetImmerse/Gamebryo mesh file format. Blender/3DstudioMax cannot open file without plugin
DDS: Texture file format. Photoshop/Paintshop/GIMP can open file directly
OBJ: Basic mesh file format. Blender/3DstudioMax/NifSkope can all work with OBJ. Doesn’t save animations/anything other than the basic mesh.