I find knoppix can be installed to hard disk and usb sticks/keys. But it seems that all these are actually making a root/ file system on the device. But the result is the same, you must customize what you want to install when you are customizing the the original compressed filesystem.
This makes sense when we are doing this for our own fun. If I want to make this easy to others' usb sticks/keys for their fun, I have to do the customization in correspond to their need. So a readonly compressed_fs does not totally fit well here. But if we make the cd with compressed fs and leave installing usb sticks/keys with normal fs or make a compressed fs dynamically if posssible, just like a installation CD, as Fedora Core or debian offer to us.
But how to make this possible?

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