The best replacement for folder is directory.

The best alternatives to folder are rated as following:
★★★★★  directory
★★★★★  file
★★★  briefcase
★★  fixed blade
★★  scruncher
★★  crumpler
★  smart folder
★  stack
★  briefcase windows
★  wadder
★  archive
★  directory windows
★  subdomain
★  package
★  binder
★  document set
★  brief case
  brochure
  project omnifocus
  drive lock
  playlist
  buncher
  branch tfs
  itunes music folder
  album iphoto
  tlr
  file folder
  envelope
  neck knife
  sub domain
  archive folder

Your alternative for folder is not listed? Suggest!
Speaking about folder, one probably shouldn't forget about question mark.

Other search terms related to folder and their ratings are:
★★★★★ question mark
★★ exclamation point
★★ clipboard
★ notepad
★ question mark macbook
★ exclamation mark
You have in mind a companion for folder and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of folder in all years. Click on graph for more.
folder
directory
file