Here is how I'm trying to measure this on my system: (for d in `find / -type d | sed 's/[^\/]//g'`; do echo $d | wc -c; done) | sort -n Edit: It looks like

Here is how I'm trying to measure this on my system: (for d in `find / -type d | sed 's/[^\/]//g'`; do echo $d | wc -c; done) | sort -n Edit: It looks like the deepest directory on my (Mac OS X) system is 27 directories deep.