debian12yrold writes "At our school, we have been assigned laptops that run a copy of Windows XP. I have asked the helpdesk in our school to set my BIOS up so that it boots from a CD, for the purposes of trying and testing various Linux discs. What I would like to be able to do, is get a LiveCD that will tell my computer to boot up of an image on an external hard disk. Although this setup would allow me to boot up off a custom image, it would not allow me to edit or alter the custom image while I used it (LiveCD versus Hard-disk install). The ideal solution for this would be a system where the boot-loader could act like a wrapper around the image, tricking the OS into thinking that the image is a HDD (without the virtualization speed penalties). Does the Slashdot community know of any system that would allow me to do this without any speed penalties?"