I put my backpack containing my laptop in the milk crate that I have attached to my rack everyday. I've been doing this since May of this year and haven't had a problem. As long as the computer is shutdown and not suspended or hibernated you should be ok. The hardware in laptops is usually pretty secure so I wouldn't expect any components to shake loose. The LCD screens seem be able to handle the vibrations with no problems. The main thing is to make sure the hard drive isn't spinning, hence the need to shutdown.