Anonymous Monk,
You have already been given the answer to your question, some references for more information, and a classic example (dispatch tables) of when you might use anonymous subs. I will offer my favorite - closures:

#!/usr/bin/perl
use strict;
use warnings;

sub countdown_iterator {
    my $start = shift;
    return sub { $start-- };
}
my $countdown = countdown_iterator( 10 );
while ( my $time = $countdown->() ) {
    print "T - $time\n";
}
print "Blast off\n";
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