An ideia to get this forum rolling: each of us has it's own design preferences. Could be cool if we shared our toolset - our favourite applications to create 3D and VRML/X3D content.
Here's mine. I prefer free/open source/shareware tools whenever possible.
Vivaty Studio: who doesn't know this amazingly versatile program?
Google Sketchup: another app that needs no introduction. Awesomely simple to use and create cool buildings.
Bryce: an old name in 3D, Bryce is very useful to create skybox backgrounds and terrain meshes. It's a pity that it does not allow exporting other 3D meshes.
CB Model Pro: organic modelling can be daunting, yet this app makes it a very simple process. Very good to create organic meshes. Now incorporated into Dassault Systèmes 3D Via, it can still be downloaded as a standalone beta application. Beware: can generate meshes with high polygon counts and is prone to crashing (it is a beta software), but it's worth the effort.
Doga L3: cute japanese app specifically created to ease learning of 3D workflow. Complex models can easily be assembled from a library of parts and then exported as DXF or VRML files. Very useful for tech meshes, vehicles, robots, mechas and other cool sfi-fi stuff. And animals.
Avatar Studio
Meshlab: when Vivaty fails to import external content... meshlab to the rescue. This is a free 3D file format conversor, with a dazzling array of formats to convert to - from the most generic (OBJ, WRL, DXF) to the exotic (PLY). I use it to convert collada or kmz files from Sketchup when Vivaty fails to import them properly.
Gimp and Inkscape: an image editor to edit/paint textures and a vector drawing program to create images. Both free and very complete.
Stuff that i play with but haven't found yet a way to integrate in the workflow: Makehuman, still in alpha, an open source Poser clone that shows great promise to create realistic characters, and Autodesk 123D, a sort of google sketchup for 3D printing that might be useful to model meshes for VRML/X3D.
And now, your turn! Share!