[Multiplying numbers]

but this is too slow.

My first reaction to anyone saying that basic arithmetic is too slow in Perl is: are you sure Perl is the right language to solve your problem in?.

i would like to hear an 'outside the box' opinion :)

Here's an outside the box opinion:

    use autodie;

    my @a = (230000 .. 900000);

    $ENV{BC_LINE_LENGTH} = 1 << 31;

    open my $cld, "|-", "bc";
    local $" = "*";
    print $cld "@a\n";
    close $cld;
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Now, that gets you an exact answer. And is certainly "out of the (Perl) box". It may not be the fastest. If you need the fastest solution, I'd look into PDL. It's made for stuff like that. Alternatively, I'd port FORTRAN to Parrot, write a FORTRAN routine to calculate the product, then call the FORTRAN routine from a more familiar language that also runs on Parrot. But the PDL way may be easier.