Przygotowanie patyka (zakładam, że na urządzeniu /dev/sdx jest jedna partycja :)):

$ mkfs.vfat -n patyk /dev/sdx1
$ mount /dev/sdx1 /mnt/
$ grub-install --no-floppy --root-directory=/mnt /dev/sdx

Zawartość pliku /mnt/boot/grub/grub.cfg:

set menu_color_normal=white/black
set menu_color_highlight=black/green

# --

menuentry "grml-medium 2011.05" {
	# iso url: http://download.grml.org/grml-medium_2011.05.iso
	loopback loop /iso/grml-medium_2011.05.iso
	echo  'Loading vmlinuz...'
	linux (loop)/boot/grmlmedium/linux26 findiso=/iso/grml-medium_2011.05.iso apm=power-off boot=live nomce noeject noprompt ignore_bootid 
	echo  'Loading initrd...'
	initrd (loop)/boot/grmlmedium/initrd.gz
}

menuentry "grml64-medium 2011.05" {
	# iso url: http://download.grml.org/grml64-medium_2011.05.iso
	loopback loop /iso/grml64-medium_2011.05.iso
	echo  'Loading vmlinuz...'
	linux (loop)/boot/grml64medium/linux26 findiso=/iso/grml64-medium_2011.05.iso apm=power-off boot=live nomce noeject noprompt ignore_bootid 
	echo  'Loading initrd...'
	initrd (loop)/boot/grml64medium/initrd.gz
}

# --

menuentry "PLD Rescue x86" {
	# iso url: http://rescuecd.pld-linux.org/download/2011-02-12/x86_and_x86_64/RCD_11_02.iso
	echo  'Loading vmlinuz...'
	linux /rcd/vmlinuz
	echo  'Loading initrd...'
	initrd /rcd/rescue.cpi /rcd/custom.cpi root=/dev/ram0
}

menuentry "PLD Rescue x86_64" {
	# iso url: http://rescuecd.pld-linux.org/download/2011-02-12/x86_and_x86_64/RCD_11_02.iso
	echo  'Loading vmlinuz...'
	linux /rcd/vmlinuz6
	echo  'Loading initrd...'
	initrd /rcd/rescue6.cpi /rcd/custom.cpi root=/dev/ram0
}

# --

menuentry "Memory test (memtest86+)" {
	linux16 /misc/memtest
}

# --