File (hook_file) Backport to d6

I've recently committed the File (hook_file) module, which is an experimental backport of file.inc from Drupal 7 to Drupal 6. From the project page:

This is an experimental backport of Drupal 7's file.inc "hook_file" API to Drupal 6. Things work the same, except anywhere you would call a file_xyz function, you would call hook_file_xyz. Also, anywhere you would implement hook_file_xyz, you would instead implement hook_hook_file_xyz. This would give modules the new functionality, and when ultimately upgrading, developers would replace the functions by simply changing all occurrences of "hook_file" to "file".