Nice post to get myself some practice in benchmarking. Here's my try: 
#!/usr/bin/perl

use Benchmark qw(cmpthese);
use List::Util qw(reduce);
use Inline 'C';


cmpthese (-5,
    {
        'initial' => sub {
            my @numbers = (2,3,4,5);
            my $total = 1;
            for(@numbers){
            $total = ($total * $_);
            }
        },
        'listutil' => sub {
            my @numbers = (2,3,4,5);
            reduce{ $a*=$b } @numbers;
        },
        'eval'    => sub {
            my @numbers = (2,3,4,5);
            eval join "*", @numbers;
        },
        '*='     => sub {
            my @numbers = (2,3,4,5);
            my $total=1;
            $total *= $_ for @numbers;
        },
        'reducing'     => sub {
            my @numbers = (2,3,4,5);
            $numbers[0] *= pop @numbers while ( @numbers > 1 );
        },
        'inline'   => sub {
            my @numbers = (2,3,4,5);
            multiply( \@numbers );
        }
    });


__DATA__
__C__
double multiply (SV * terms)
{
    I32 numterms = 0;
    double res = 1.0;
    int i;
    if ((!SvROK(terms))
        || (SvTYPE(SvRV(terms)) != SVt_PVAV)
        || ((numterms = av_len((AV *)SvRV(terms))) < 0))
    {
      return 0;
    }
    for (i = 0; i <= numterms; i++) {
        res *= SvNV(* av_fetch((AV *)SvRV(terms), i, 0));
    }
  return res;
}

[download]
the results: 
             Rate   eval reducing  initial       *= listutil   inline
eval      21683/s     --     -84%     -84%     -85%     -85%     -89%
reducing 134819/s   522%       --      -4%      -6%      -7%     -31%
initial  139854/s   545%       4%       --      -3%      -4%     -28%
*=       144019/s   564%       7%       3%       --      -1%     -26%
listutil 145100/s   569%       8%       4%       1%       --     -25%
inline   194405/s   797%      44%      39%      35%      34%       --

[download]
If I'm doing something wrong here, please correct me.

In reply to Re: Multiplying together the numers in an array by eXile
in thread Multiplying together the numers in an array by Cody Pendant

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