Would the kernel revisions really have to be distributed as source? Perhaps they could be
distributed as pre-compiled object files. This would be much quicker for testing, might do
away with the need for scratch space (if there was enough RAM available for linking), and
space could still be saved by only including the object files which had actually changed since
the last revision in a particular revision on the live CD. kexec could be used to load the
newly linked kernel.