I'd do the duplicate elimination in the outer loop: 
while (<DATA>) {
  chomp;
  my $key = lc $_;
  next if $seen{$key}++;
  my $signature = join "", sort split //, $key;
  push @{$words{$signature}}, $_;
}
for (sort keys %words) {
  my @list = sort @{$words{$_}};
  next unless @list > 1;
  print "@list\n";
}
__END__
Abby 
abbot 
acne 
alert 
alter 
baby 
Baby 
BABY 
best 
bets 
cane 
later 
Unix 
UNIX

[download]

-- Randal L. Schwartz, Perl hacker

In reply to Re: Perl's pearls by merlyn
in thread Perl's pearls by gmax

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