Make mousing over a new window or screen change the focus to that window? [duplicate]

Solution 1:

I made a python script that does this. Check it out: https://bitbucket.org/sivann/mac-screenfocus/src

It focuses the last app that had the focus before the mouse left the screen. No mouse clicks happen behind the scene :-)

In my setup, the external monitor is on the left, it may not work in the reverse, let me know..