Per AJR:
Knoppix is a Linux distribution and runs Linux without installation to a
HD - It is an excellent "tool" for recovery. A "complete" version of XP
cannot be run from a CD - BartPE "copies" a minimum XP files to provid for a
troubleshooting environment.

But doesn't it need at least some hard drive space somewhere?

Seems like it stores info between boots... or am I imagining
that?
--
PeteCresswell