Hi, to extract the contents of an iso file, mount it...
(the directory must exist, if not create a directory first.)
mount -t iso9660 -o loop filename.ima /some/mount/point
Like this (works on my system),
mount -t iso9660 -o loop livecd-i686-installer-2008.0-r1.iso /media/hd
Then copy the contents of /some/mount/point/ to the flash drive.
With the slax setup, you onl;y need to run a script to make it bootable.
Only one more step is needed to make Slax boot from your USB device or disk: you have to manually navigate to the newly created /boot/ directory and run bootinst.sh script (if you are in Linux) or bootinst.bat script (if you are in Windows).
Maybe vector has this too. Google "frugal" for more about small installs.
Hope that helps.