>> I'd think you'd need something like a log-structured file system to do this
>> effectively.
>> 
>nope...
>
>there are several companies in the valley that are working on this.
>though I'm not at liberty to say who or what projects. and i'm not
>a filesystems person. but, from what i've seen (looking at the filesystem
>code) it could be done. though, the places are limited where this would
>work.                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 ^^^^

Like I said ... you'd really need to have a log-structured filesystem
to do this effectively.  (I suppose you _could_ build all of fsck into
the kernel, but that would be nasty ...)

--Ken