I just want to say what a great help this was in finding my iTouch device serial number S/N after it was stolen and I couldn't find my original box or manual. It also shows tons of other info about the version and other identifiers when you cntrl click the about section. Only problem is you need a stop button as it scrolls by...lol...I had to do it like 10 times to get all the info I needed.
Kk try this open iTunes. Then click the menu tab "iTunes". Then hold down the control key while you're clicking onto "About iTunes". Now you you see a slightly modified About iTunes page, with contains the serial number of your last connected devices. (last iPod and last iPhone). If you see the numbers, press the spacebar, so the screen doesn't move anymore and you can write your serial down.
The answer that is shown below or above my window really works
Yeah as the answer above said, but I got reallly confused because it wasnt working, if your on vista, you may have to try both Ctrl seperately keys before it works :-)
1a931c6a201