>   I have /scratch mounted on /dev/sd0f. Now and then (indeterminate 
>   times, but *maybe* around 2:00am fsck) I lose a bunch of files 
>   in the directory (even lost a recent set of -current tarfiles..).

>   And another thing - as far as I can tell, the problem is affecting
>   just the one partition, /scratch... This partition used to be /usr,
>   and was in use as such for about 5 months, with no problems at all.
> 
>   What could be wrong?

See the following code in the daily cron script:

	if [ -d /scratch -a ! -h /scratch ]; then
	        cd /scratch && {
        	find . ! -name . -atime +1 -exec rm -f -- {} \;
	        find . ! -name . -type d -mtime +1 -exec rmdir -- {} \; \
	            >/dev/null 2>&1; }
	fi

I'd pick a new mount point for your partition, or remove that section
from /etc/daily.

	--jtc