having a single mounted folder pointing to different paths would make easier to have a maintaining system, i meant to have apache, SDL, and mplayer installed into their own folders (/usr/local/mplayer, /usr/local/SDL and /usr/local/apache) but the mounting system could have mounted those three paths into /usr, in a maths way this would be something like
/usr = /usr/local/mplayer + /usr/local/SDL + /usr/local/apache
this would make easier distributing data like if some files are created directly into /usr, those files should be stored into the three original paths. mirroring and distributing databases would be simplier and I think this would have some other good things to provide.
unionfs
Take a look at unionfs. I've never tried it, but the Linux Journal article is intriguing.
Take a look at GNU Stow ;-)
Take a look at GNU Stow ;-)
a link for those too lazy to Google
http://www.gnu.org/software/stow/
is like stow but more complex
i think what he/she says is more complex than what stow means to be, since this will make stow may be useless, this would add the posibility of mirroring or backup files automaticly
this would mean that if one of the alter-directories is a NFS mount or a smbmount point, then the same file (lets say a mysql database files) would be backed up as soon as it is modified, then if the harddisk fails this files could be restored from the backups by remounting the directories from NFS and smbmount directories.