I've seen tweaks to windowsXP Home (I think) that allow you to set the number of
blinks -- but I'm not sure if that allows your code to activate a different
window.
I'm betting that you're going to need some API calls (way beyond me).
If I needed this, I'd either search google in the VB (not VBA groups). Or post
a question in one of the VB groups. Explain that you want to accomplish this
from Excel's VBA. Include your version of windows and Office.
You could search Randy Birch's VBNet at:
http://mvps.org/
or go directly:
http://vbnet.mvps.org/
Good luck.