Linux Live CD and Boot Menu

label linux
kernel vmlinuz
append vga=normal initrd=initrd.gz ramdisk_size=15000 root=/dev/rd/0 devfs=mount,dall rw

Build Your Own LiveCD or Live
http://en.gentoo-wiki.com/wiki/Build_Your_Own_LiveCD_or_LiveDVD
title=LiveCD
kernel /boot/vmlinuz real_root=/dev/loop0 looptype=squashfs loop=/livecd.squashfs vga=ask initrd udev nodevfs cdroot dodmraid
initrd /boot/initrd
title=LiveCD NO-FB
kernel /boot/vmlinuz real_root=/dev/loop0 looptype=squashfs loop=/livecd.squashfs initrd udev nodevfs cdroot dodmraid
initrd /boot/initrd
title=Memtest86+
kernel /boot/memtest86plus/memtest.bin

[SOLVED]HOWTO liveUSB with grub and serial console support
http://forums.gentoo.org/viewtopic-t-763379-start-0.html
title=USB disk - Serial Console
root(hd0,0)
kernel /isolinux/gentoo root=/dev/ram0 init=/linuxrc slowusb looptype=squashfs loop=/image.squashfs cdroot console=ttyS0,115200
initrd /isolinux/gentoo.igz

title=USB disk - Terminal
root(hd0,0)
kernel /isolinux/gentoo root=/dev/ram0 init=/linuxrc slowusb looptype=squashfs loop=/image.squashfs cdroot vga=791
initrd /isolinux/gentoo.igz

U盘安装各种Linux发行版
http://wenku.baidu.com/view/dd8a0b5e804d2b160b4ec0a1.html
root=/dev/ram0
root=/dev/rd/3
root=live:CDLABEL=UDISK
livecd=livecd