Yeah, so the only custom aspect is this alias in my .bashrc:

  fetchplay() {
      git annex get "$@" && vlc "$@"
  }

Combined with the keybindings that ship with fzf, I can type "fetchplay [CTRL-T]", select some subset of the directory tree, and the files will play. Git annex will locate the files (in this case, on another machine in my apartment) and fetch them before playing only if needed (if they are already present, "git annex get" verifies that and exits silently). I have my music collection backed up on several different forms of removable media, across several machines, and on AWS S3.

Here is a recording of me fetching and playing three tracks:

https://asciinema.org/a/t0BfyKhU4PTAenwNH79IPzqD3