fswatch:
- is a utility to guard changes in a file system.

- is composed of three simple programs: fswbuild, fswcmp, fswshow. fswbuild
  builds a file system information database. fswcmp compares two database files
  and returns what changes a in file system have been introduced. fswshow shows
  contents of database file. a file information database is platform
  independent.

- can collect the following information about files (and directories): inode,
  links, uid, gid, mode, size, flags, ctime, checksum (sha1) ; and can show
  which files were added, deleted or changed.

- is one of many similar utilities. the main difference is the configuration.
  you can define different settings for every directory in a directory tree.
  moreover, it is very small and fast.

WWW: http://fswatch.sourceforge.net