Linux is a clone of the Unix kernel, written from scratch by Linus Torvalds with assistance from a loosely-knit team of hackers across the Net. It aims towards POSIX and Single UNIX Specification compliance. It has all the features you would expect in a modern fully-fledged Unix kernel, including true multitasking, virtual memory, shared libraries, demand loading, shared copy-on-write executables, proper memory management, and TCP/IP networking.
Finnix is a small, self-contained, bootable Linux CD distribution ("LiveCD") for system administrators, based on Debian testing. You can use it to mount and manipulate hard drives and partitions, monitor networks, rebuild boot records, install other operating systems, and much more.
G4L is a hard disk and partition imaging and cloning tool. The created images are optionally compressed, and they can be stored on a local hard drive or transferred to an anonymous FTP server. A drive can be cloned using the "Click'n'Clone" function. G4L supports file splitting if the local filesystem does not support writing files larger than 2GB. The included kernel supports ATA, serial-ATA, and SCSI drives. Common network cards are supported. It is packaged as a bootable CD image with an ncurses GUI for easy use.
Loonix is a custom Linux distribution meant for server applications. It comes with only the latest up-to-date programs and applications, all specially configured for optimal performance and ease of use. Programs are neatly organized in structured directories, and strict security rules are in place for sensitive configuration files and other data.
openMosixLOAF (openMosix Linux-On-A-Floppy) is a single floppy openMosix Linux mini-distro designed for harddiskless systems or HPC clusters where only CPU and memory is needed. It has drivers for all PCI Ethernet NICs that the Linux kernel has support for (10/100/1000) and comes on only one bootable 1.6MB 3½" floppy diskette, ready to be a node in your HPC cluster.
Gentoox is a 'port' of Gentoo Linux to the Xbox. It comes in Pro and Home flavors, where Pro is a Stage 3 bootable distribution with nothing else added (for developers and pros to customize themselves), and Home comes with many packages precompiled and installed, making it ideal for beginners or people who want their Linux to work straight out of the box. Installation time is minimal and totally fuss free.