I wrote this YEARS ago, to help recover windows that would frequently disappear off screen (XP and nvidia had issues), to resize windows that were never meant to be resized, and also to quickly work with windows across multiple monitors. It never occurred to me to share it until now; it's very bare bones, but if it's well received here, I'll add some visual aids, I might take the time to rewrite this in a proper programming language.
AHK Source: https://github.com/L.../Window%20Tracer.ahk
x64 Binary: https://github.com/L.../Window%20Tracer.exe
How it works: This script operates on the active window. Hold down the configured modifier key (default: xbutton1, the "back" button on many mice) and click the left mouse button. While still holding both the left mouse button and the modifier down, move your mouse anywhere, and let go of the left mouse button, then the modifier. The point at which you clicked the left mouse button is the new top left coordinate of the active window, and the point you let go of the button is the new bottom right coordinate (or the other way around, depending on which way you moved the mouse relative to the window's previous coordinates). In short- you both resize and move the window in one swift action. Trace windows into empty spaces of your desktop! Have a lot of windows open across multiple monitors and you can't easily tell where the window you just alt tabbed to is? Trace it into view!
Video demonstration: http://1drv.ms/1H8zK8S