I would like to do the following:

Boot from a small CD or diskette with a full system coming from USB device (stick or harddisk).

1) Booting from CD/diskette is still more universal than booting directly from USB
2) I would prefer to have a "real" Linux on a second device, with persistent home and the chance to persistently apply changes to the system (patches, new software, config etc.)

I have browsed in the area of syslinux/isolinux and in many magazines. Unfortunatley in most cases they deal only with a "full USB" boot (in most cases mounting a fixed Linux filesystem image).

I am sure this canīt be so hard. It may look like (1) start boot from CD, (2) mnt USB device, (3) "point" to Linux system on USB device and the work with the "real Linux on the USB device.

I need to know
a) what to put on the CD (sorry not only in rough "building blocks"....) and
b) how to prepare my USB device (FS, content (preferably just copy the Knoppix-CD filestructure))

Any help?