if i want to add some logic bricks to 100 objects, all the same, or if i want to mark the edges, unwrap, create an image an bake, this for 100 cubes, do have i to repeat it 100 times or can i tell blender “do what i’m doing to this object to all these others 99 too”??
thank you in advance… 
you can make it in one object nd duplicate it by pressing Ctrl+D then all your objects will be like clones of the first duplicated one!
i know, but the fact is that these objects are positioned and scaled, etc, and duplicating an object and repositioning and rescaling this object’d be a harder work… 
hope there is another way
PS: and the fact is that the bake is different for every object, depending on the position (for the light)… so the process is the same, but the result different…
you can bake them all togheter, but i think that this ll not be very good because you ll have a big texture on each object
… and how would i be able to bake them all toghether, without joining them?
anyway, the only thing i really thing can work is, as i said, a way to do this on an object and repeat it to all the other objects… i hope blender has somewhat like that, else it’d be a huge huge work…
You can copy properties and logic bricks with <ctrl><c>.
If all (or some) objects share the same geometry, you can make them share the same mesh (similar to <Ctlr><d> mentioned earlier. With this method, you keep the object transformations (position/orientation/scale).
You can do this by <F9> editing buttons, panel “Link and Materials”, click on “ME:” chooser and choose the mesh to the one you want to keep. You can change this one mesh and it will be shared by all object linked to this mesh.
Unfortunatelly you have to change the mesh 99 times. I do not know a shortcut for that.
Edit:
You can change the mesh with cut&paste
That should be quite fast.