Way back in the mysts o’ tyme, indeed on another site altogether, I told a tale of a little picture-in-picture / interactive zoom tool I was working on. Not a massive project, just a little something that would sit in the corner of the desktop and allow me to play around with and keep an eye on a different windows. Usually I use it for keeping an eye on things from video sites which you can follow without giving full attention or for transcribing things without having to keep flicking back and forth between windows.
Anyway, a whole year and 4 months after it was ‘nearly finished’, I got round to fixing the buggy bits and wrote some help pages for it. Now (I think) it’s ready for public consumption as an Installer, or just a Zip (file hashes are on the info page if you want to verify).
From there you can interact with the source window just as you would the real one with mouseover effects, button clicks etc. But that’s a bit boring, and with large windows the contents are kinda small, so what you can do is select an area
If you prefer to see it in moving action, I whipped up an ‘ad’ for it.