Backshift is a deduplicating (variable-sized, content-based blocks), compressing (xz or bz2) backup program. Full saves and incrementals are pretty indistinct other than the amount of data transmitted, somewhat like with "rsync --link-dest" but without the huge number of hardlinks. It also de-duplicates large file content at a granularity of about 2 megabytes on average; there tends to be a unique copy of each file with size less than around 2 megabytes on average.
neko-install-cd is a development tool for modifying System Rescue CD images. It can also perform many other operations. It has a simple interface with excellent inline help. Operations it can perform include: booting your modified image in a virtual machine, burning the original or modified image to a USB drive, creating patch sets from your modifications (using aufs or built-in helper scripts). All of these operations can be performed directly from your Linux distribution, without having to first boot into the system rescue CD as with the system rescue CD equivalents.