GaryOS 3.0

http://sourceforge.net/projects/gary-os/
GaryOS is an open source and freely distributed operating system based on the Gentoo and Funtoo Linux distributions and designed from the offset to provide users with a complete rescue system in a single binary file. It also borrows elements from the Grml Linux distribution.
Features at a glance

GaryOS offers an entire Funtoo- and Gentoo-based operating system that includes a toolchain and resides in RAM (system memory), which means that you can eject the bootable medium after boot.

It features support for Microsoft Windows, GRUB and PXE (Preboot eXecution Environment) bootloaders, a Forensics mode that requires no disk drives or swap, has a small footprint, and doesn’t require a CD/DVD media to work (it can be deployed on a USB flash drive).
Distributed as bootable kernel files

Currently, GaryOS is distributed for free as bootable files with the .kernel extension, one for each of the supported hardware platforms, 32-bit and 64-bit. The binary files include initramfs and a Linux kernel, and have been generated using the Metro automated build tool with a a customized Gentoo/Funtoo configuration.
Getting started with GaryOS