my (%word, %gram);

while (<>) {
    chomp;

#     $_ = lc $_; 					
    /[^a-z]/ and next;
    my $sig = pack "C*", sort unpack "C*", $_;

    if (exists $word{$sig}) {			 

        if (exists $gram{$sig}) {
            next if $gram{$sig} =~ /\b$_\b/; 
            $gram{$sig} .= " $_";            # rare
        }
        else {
            next if $word{$sig} eq $_;
            $gram{$sig} = "$word{$sig} $_";  # rare
        }
    }
    else {
        $word{$sig} = $_;                    # mostly
    }
}

print join "\n", (sort values %gram), '';    # just output short list