Hrm. If you want to have Perl restructure your hash, I'd do it in the following way:

sub make_ext_hash {
  my $mime = shift;
  my %ext = ();
  for my $name (keys %$mime) {
    my $desc = $mime->{$name};
    $ext{$_} = {
      icon => $mime->{$name}{icon},
      name => $name,
    } for @{ $desc->{ext} };
  }
  return \%ext;
}
[download]

That seems pretty straight-forward to me.

Update, as per the cb:

sub make_ext_hash {
  my $mime = shift;
  my %ext = ();
  for my $name (keys %$mime) {
    my %hr = (
      icon => $mime->{$name}{icon},
      name => $name,
    );
    $ext{$_} = \%hr for @{ $mime->{$name}{ext} };
  }
  return \%ext;
}
[download]

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Jeff[japhy]Pinyan: Perl, regex, and perl hacker, who'd like a job (NYC-area)
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