On Thursday 03 April 2008, Oren Beck wrote:
"The Zen of Everything being a file" so far has not covered the WHERE we put the files!
Sure it has.
Anyhow, you should define what you mean by "data".
/usr should always be read-only OS files-- it's generally considered safe to mount it read-only in everyday use. /usr/local is another matter, if you use it, and not as well defined.
More read-only OS directories: /bin /boot /lib /sbin
Configuration should all be in /etc, /usr/local/etc (on some OS), and /home/*/.*
User data will always be in /home/* (or /root for root of course).
Daemon data is kept in /var