I can think of a 'poormans install', you basicaly copy the big Knoppix compressed-drive onto your HD. You can extract the floppy-image and run the kernel via lilo (bootmanager) or loadlin (DOS). It will run exactly like from the CD-ROM, you won't be able to add anything, etc. There is some documentation about this floating around in this forum (and probably the docs too).

I can also think about a less drastic knx-hdinstall script which extracts the compressed-drive image but doesn't disable the scripts. But I think you would need to patch the boot scripts in a lot of places to make it more like Debian (so you can use apt-get), not using the cloop and ramdrive, etc...