Several packages for creating rescue disks are available on metalab.unc.edu. With these packages you specify a set of files for inclusion and the software automates (to varying degrees) the creation of a bootdisk. See http://metalab.unc.edu/pub/Linux/system/recovery/!INDEX.html for more information. Check the file dates carefully. Some of these packages have not been updated in several years and will not support the creation of a compressed root filesystem loaded into ramdisk. To the best of our knowledge, Yard is the only package that will.