transform.position ,......

How can i make a gameobject move from point A to point B at a specific speed and than move back to point A at half of that speed and keep on doing that(looping)?

Check out iTween for Unity... It has this feature, and also, you can get the visual editor for it as well...

http://itween.pixelplacement.com/documentation.php

http://dkoontz.wordpress.com/2010/10/27/itween-visual-editor/

Hope that helps!

Edit: But, if you want my way of doing it... Add 2 empty game objects, make their tags something unique... Then, have an object spawn at one of the tags (Can be random or not), then have it find another object with that tag, then have it move to that object, and have an if statement, if Player (Or w/e is moving, again, you can use the tag finder), is within __ (Get the distance), then find new object, and in the update function, put in the move to destination script...

Hope that helps a little bit atleast.