Just blew away Red Hat 9 and installed Knoppix 3.4 to hdb on my old 500MHz box. Awesome. Thanks to Fabian and Kano for an excellent install script, and to richenbacherus for the info on editing /root/.knofig to get a separate home partition going.
It's not much faster starting KDE, but it is faster running KDE than RH was. (Then again, I upgraded RH 3 times, so there was bound to be lots of cruft).
The only really weird thing is that QTParted says my partition layout looks like this:
* = hidden 0.03M partitionsCode:|*| |-------------- hdb2 ---------------| |---- hdb1 ----| |-hdb3-| |*| / /home swap
Never seen anything quite like it. These two hard drives have been through multiple partitioning and OS changes, however.

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