Thanks Eric. I thought about the Timer idea. It feels so kludgy, and like such a waste of resources. There are design-paths around this issue, but I would hate to rework the design of all the existing forms for which I need this.
Another thought is to capture, at the form level, all key presses and mouse movements, and on each one, check the active control, and if it has changed, take the action. Again, that just feels odd, and I keep hoping there's another way.
The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts. - Bertrand Russell