Using Milkshape 3D with Unity?

I'm looking to create a purely 2D game and it looks like the best way is to create a 3D game with an orthogonal camera. So, I'll need something to create some basic models and can't afford tools like 3DS Max and Maya. Will Milkshape work for this task or is there a better route I should go about?

You could use Blender... it's free, and fully supported by Unity.

But you don't necessarily need to make 3D assets for use in a 2D game... depending on the context of what kind of game you're making, you could make 2D assets in Photoshop or whatever, and then use plane primitives along with standard box colliders. Rigidbodies (physics) and other items work equally well on 2D planes as they do on 3D items. :)

Edit: The bottom of this page lists all the file formats that Unity is compatible with: