CPAN LINK: Acme::Comment
CPAN ABSTRACT: This module allows for multi-line comments which are filtered out. Unlike the pseudo multi-line comment if (0) {}, the code being commented.
Introduction:
Roaming about the monastery I came upon the following node: Block Commenting, a fellow monk essentially searching for advise on the possibilty of multi-line commenting. A few replies down mentioned in passing the module Acme::Comment, it's claim was to allow multi-line comments which are filtered out. I became curious so I downloaded the module and checked it out for myself.
Functionality:
Acme::Comment, in a nutshell, allows for multi-line and single line commenting in several different language styles. Some of the multi-line comment language styles are: C++, HTML, Pascal and Java to name a few. In total, both single and multi line together there were a total of 43 different programming languages represented. I tested it out in "HTML" mode using multi-line comments with ActivePerl 5.8.0 on WinXP, and it proved to be quite easy to use. The distribution itself contains fairly straight forward documentation.
Generic Example: 
#!/usr/bin/perl -w

use strict;
use Acme::Comment  type=>'HTML';

<!--
Multi-line comments here.
Everything enclosed in the html
style comment braces is ignored.
-->
my $a=1;
my $b=2;
my $c=$a + $b;
print "$a + $b = $c\n";

[download]
Final Thoughts:
For implementation of multi-line comments in various language formats I found this module to be quite useful. The only drawback that I can immediately see is that this module is not yet widely known. I think multi-line commenting (a single format of) would be great implemented as a standard feature in a future version of Perl; perhaps in Perl6? (it can't hurt to hope)

In reply to Acme::Comment by PERLscienceman

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