Hello again...
I was just testing my screensaver on a machine with 2 monitors, and the background of both went black (as set), but the images jumped over the 2 monitors.
Example:
pic1 on screen1
pic2 on screen2 while still showing pic1 on screen1
pic3 on screen1 while still showing pic2 on screen2
pic4 on screen2 while still showing pic3 on screen1
etc.
And with a flash element, it only showed on the moniter which is set as 'first monitor'.
So I was thinking, some kind of 'copy monitor1' function, so that it showes the exact same thing (or not) on both screens (at least in the case of Flash).
I have no clue if this is even possible, but it's just something which I noticed.
(a tiny note, due to some misconfiguration on the machines side, the 'first' and the 'second' monitor were somehow switched), and monitor 2 was turned off, so nothing showed on monitor 1 [set as second] )
^the above note might be confusing...