There was a topic about sort of the same thing, but from 2007.
I think it'd be a neat feature to have a "save wand". It would select bricks the same way the duplicator wand does, except that you could continue adding to the selection. An example of this: Click a baseplate to select all the bricks on it, they turn invisible like when selecting with the duplicator, then you can go and hit a different baseplate and have it added to the selection. There would need to be a way to clear your selection, maybe click the ground or dropping the item.
After you have made your selection you can save from the menu (a save selected bricks only check box maybe?).
Also, on a related note:
As far as i know, there is no way to change where on the map bricks load. I agree with this, as it is a nice thing to rely on.
However, if I'm loading a small build on a map(slate) that already has builds scattered around, I have no idea where it will load. Also, moving to bedroom/nonflat maps to slate edits or vice-a-versa you can run into problems with your build loading correctly or accessibly. While this is a minor inconvenience, what if when loading you could move around a ghost of all the bricks that touch the ground (as one ghost)? You then could force the build to load where you needed it to. This feature could be selected from the load menu with a check box.
Obviously this load feature would not be practical with large saves. I would probably only try to use it with the size saves that i used the save wand to save with.
After typing all that, I don't really think it could be accomplished with a third-party add-on, however I admit I do not know the limits of add-on creation...
If not an add-on, perhaps a considered feature for future versions/releases of BL?
Also, if it would require huge amounts of code/engine/something reworking, I can sit down and shut up :)
