How to create a mirror?

Assume that we have a Cube object in our scene.
How to make its surfaces reflect the scene as if it is covered with mirrors ?

-Adamo-

I guess the only way to do this is by using rendertextures? For each surface, create a camera that mirrors the “players” camera-position through the line of the surface. Each mirror-camera renders to a rendertexture, that is displayed on the corresponding surface of the cube.

I am novice Unity user.
Is’t it possible to create a reflective material and assign it to the cube in Unity?
This is what I would do if I work in Cinema 4D or 3D Studio etc. But I don’t know how to create a reflective material in Unity.

There’s the reflective material shader, but that’s essentially environment mapping, it’s not real-time reflections. In Unity Pro (at least 2.x, haven’t tried in 3) there’s this method to get real-time reflections: http://www.unifycommunity.com/wiki/index.php?title=MirrorReflection2