Just for Reference…
Do you need to re-path x-refs for a large number of drawings? A quick and easy way to accomplish this is by using the Reference Manager application. Go to your Windows Start menu, click Programs, then Autodesk, then AutoCAD, and you’ll find the Reference Manager application. Click the Add Drawings button, and the program will show you the data for each of the selected drawing. Once you select the necessary attachments, you’ll be able to edit a path or perform a Find and Replace on them.
For a first look at how'd you'd go about programming something yourself, using lisp and scripts, check out this class called "Changing Hundreds of AutoCAD Drawings in a Hurry."
Working in a large hospital, our projects are usually a pretty small part of each massive floor plate, so we use the XCLIP command quite a bit to omit irrelevant extents of a plan. Did you know that, since AutoCAD 2008, you can invert the clip selection, cutting a hole in your existing plan that you can fill in with new data?
Selecting the xref will bring up the contextual External Reference ribbon tab. Select Create Clipping Boundary, select Invert clip (or type I), then select a polyline boundary or drag a rectangle around the needed area.
To move a Tool Palette out of your way without having it dock on the edge of your screen, simply hold down the Control key while you’re moving it and it will remain floating.