README

1. you should install LWP::Simple and Fuse:Simple - use cpan or cpanm
2. you should configure the local fuse install to run as root or as common user
3. don't forget 'fusermount -u <mountpoint>' after finish the script

to test

$ chmod +x cats.pl
$ mkdir catfs
$ ./cats.pl catfs

# in other terminal 

$ ls catfs
cat.jpg

$ gimp catfs/cat.jpg  # will open a different kitten pic each time

# after finish the script
$ fusermount -u catfs

cats.pl

#!/usr/bin/env perl 
use strict;
use warnings;

use LWP::Simple;
use Fuse::Simple qw(main);

my $mountpoint = $ARGV[0];

die "usage: $0 <directory>\n" if ! defined $mountpoint || ! -d $mountpoint;

main(
  mountpoint => $mountpoint,
  "/"        => {
    'cat.jpg' => sub {
        get('http://thecatapi.com/api/images/get?format=src&type=jpg');
     },
  },
);