Rendering mesh edges in-game just as they appear in editor mode

Again a question about actually seeing in-game what appears in editor mode.
you know when you see a mesh in editor mode, and select it, unity3d tells you the mesh is selected by changing the wireframe of that mesh to blue
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I would love it if such thing was possible in-game.
To have the wireframe be visible/blue like that.

Do you know how to achieve it?

here are some examples how other guys did it in Unity Community:

(shader version works with free unity)

(GL version pro only)