The code above generates duplicates (i.e. the same TLD will be generated more than once). Consider:
'a'.'a'.'a'.'a'.''.''
'a'.'a'.'a'.''.'a'.''
'a'.'a'.'a'.''.''.'a'
The following does not have the duplicates problem. It could be optimized a bit (and shortened too), but I leave that as an exercise to the reader... 
#!/usr/bin/perl -w
use strict;

my @chars=(('a'..'z'),(0..9));
tld('',$_) for (3..6);

sub tld{
  my ($txt,$cnt)=@_;
  if($cnt==0){
    print "$txt\n";  
  }else{
    tld($txt.$_,$cnt-1) for (@chars);
  }
}

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In reply to RE: TLD generator by lhoward
in thread TLD generator by j.a.p.h.

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