Slurp it into a hash? ;-) 
#!/usr/bin/perl -w 
 
use strict; 
 
my %unique; 
while (<DATA>) { 
  chomp; 
  $unique{$_} = ''; 
} 
 
my @array = keys %unique; 
 
 
$, ="\n"; 
print @array; 
 
__DATA__ 
Brentwood 
Brentwood 
Westwood 
Beverly Hills 
Beverly Hills 
Beverly Hills 
Bev Hills Adj. 
Palms 
Mar Vista 
Mar Vista 
Mar Vista 
Mar Vista 
Mar Vista 
Venice 
Santa Monica 
Santa Monica 
LA/Crescent 
LA/Crescent 
Koreatown 
3rd/LaBrea 
3rd/LaBrea 
3rd/LaBrea

[download]
(of course, if you want to preserve order too, some extra cunningness will be required; but the basic idea remains the same)

In reply to Re: Detecting duplicate entries by kilinrax
in thread Detecting duplicate entries by r.joseph

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