As you (may) know, if you want to capture the active window on a Windows PC and save it as an image to the clipboard, you can simply hold down ALT+Print Screen. However, what if you are running Windows on an Apple PC, either via Bootcamp, or within a virtual machine: there is no Print Screen key on an Apple keyboard.
There are a number of ways you could do it - if you were running Windows in a virtual machine on top of MacOS, then the Apple Grab utility is very good and allows you to capture the active screen, or you could press Shift+Command+4, the cursor will change into crosshairs, move the mouse to select the area of screen you wish to capture, as soon as you release the mouse that screen area will be saved to the desktop as a PNG file (MacOS X Tiger).
However if you are running Windows natively, there is no pront screen key. The solution I have found (and I'm sure others have too), is to use the Windows on-screen keyboard (Start--> Programs --> Accessibility --> On Screen Keyboard). There is both an ALT key and a PSC key on the virtual keyboard, and the keyboard does not change the focus of the window selection.
Very handy!
James Liddiard
Network Manager