Rotate object based on mouse position

I would like to rotate an object based on the position of the mouse. I have searched a lot for this but none of the solutions seem to work. This video is about GameSalad but it shows exactly what I mean.
https://www.youtube.com/watch?v=EoyNhvqujuU

Here is a solution I know works (assuming your object is a Sprite or a Quad). It assumes that the front of the object is to the right when the rotation is (0,0,0). If you have trouble using it, make a comment, and I’ll follow up…

http://answers.unity3d.com/questions/603757/2d-mouse-aiming.html