Brian writes:

 > "Smart Replace" only replaces the files on the target
 > HD that haven't changed.

Yes, it used to be called << Exercycle Mode >>. But
that was before a Macworld survey determined that the
average new Macintosh runs at only 3% of its power(;-)

Joking aside, didn't Mac OS 9 have a utility for
keeping two copies of a volume in step. Name?
When I get my 100 Gig IDE I'll wanna maintain copies of
my dozens of volumes that way, all at a blow...

Cheers

Laurent S.