Creating Meshes and Physics Objects At Runtime

Could someone explain how to make a game object with a custom mesh at runtime? For example, if I have 8 points in world space, could that be translated into an object that I could then apply physics to? Could this new mesh be concave? Could it be re-manipulated once the mesh is created?

Any info regarding this subject would be appreciated. Thanks! :)

Have a look at the Mesh class. The mesh you make can be used in the mesh collider.

I also have a demo on the Unify Wiki on Creating a Fake Gizmo, which creates a Procedural Mesh, which may help clarify the procedure.

FYI, I created the sample Arrows by taking a Blender model and exporting it to .FBX, then wrote a Python script that extracted the vertex/triangle information, for cutting/pasting into Unity code.