In Norway you're now required to put your laptop through on its own.
However, you do not have to take it out of its protective sleeve (eg Tucano Second Skin), and you place it in a plastic tray yourself. Have also been requested to do the same at Schipol (Amsterdam), and it was done in exactly the same way.
First time I experienced this, I asked if they also wanted my iPod through seperately. It's a hard drive with electronics attached after all. Nope, that wasn't necessary.
To be honest, I don't know why the want laptops on their own but not iPods, video cameras, portable DVD players etc...