Even though I write it in 99% of my deviation descriptions, about three times a week I get comments, notes or emails asking what tools I use to create my work. Maybe this will help, but if people aren't reading the descriptions, it's difficult to believe they'll read this either.  I hope this answers your questions as it's pretty detailed.

For Most 3D modelling:
I use 3D Studio MAX from Autodesk. - [link]  I've been using 3D Studio since rel.2 running on DOS. long before it was "Maxxed". It's my go-to 3D application for modelling and rendering.

For complex, detailed and accurate mechanical modelling:
I'll use (usually in combination) AutoCad and Inventor from Autodesk. [link]  and  [link],  AutoCad is a great layout tool and you can do 3D solid modeling in it as well. I'll often do my layouts in Acad then bring those into Inventor. Inventor is a very powerful parametric 3D solids and surfaces modeler. It makes adding design features like cutouts, fillets, chamfers and more a simple affair. It's also easy to make dimension driven changes to parts within an assembly. Move a hole in a part and it will update the part that mates with it, so the holes line up. Cool huh.

For Most 3D rendering:
I use 3D Studio Max with the Vray render plug-in - [link]  It is a much loved tool for realistic material creation, lighting and rendering. It uses lots of settings and can be tricky to learn and optimize. I find it give me great lighting, DOF, reflections and can be used to create very, very complex materials.  It's what I use for really all of my 3D rendering.

For Most 2D raster work:
Photoshop - [link]  The de-facto standard. CS6 (soon to be CS7 in June). I've used it since PS2.0 running on Mac and available in grey-scale only.

For Most 2D vector work:
CorelDRAW X5 - [link] - Why not Adobe Illustrator? I have AI and use it occasionally. I prefer CorelDRAW. It does things that Illustrator just doesn't - or that it makes very awkward.  Where I can "fly" in CorelDRAW, I have to figure out a new workflow in AI to do the same thing. They play well together and can import and export compatible files, so there's no real drawback to not basing my work in AI.

Other tools:
I sometimes use Sketchbook Pro - [link] and I'm getting to like it more and more. I'll also play around with VRED - [link] for rendering. I've not found the flexibility I like from it. Plus, if I have to go back into MAX to make a geometry change, I might as well stay there and render. I'll sometimes use lightroom for image processing - but rarely.

So that's it - there's my quiver of arrows.

-Russ