This can be fairly trivially achieved with Net::POP3 and Email::MIME - the following example is not exhaustive and only partially tested (I didn't have any MIME mail in my mailbox at the time), but should put you in the right direction:

#!/usr/bin/perl
 
use strict;
use warnings;
 
use Net::POP3;
use Email::MIME;
 
my $pop3server = 'your.server.here';
my $username   = 'yourlogin';
my $password   = 'yourpassword';
 
my $popclient = Net::POP3->new( $pop3server, Timeout => 60 );
 
if ( $popclient->login( $username, $password ) > 0 )
{
    foreach my $msgnum ( keys %{$popclient->list()} )
    {
        my $msg     = $popclient->get($msgnum);
        my $message = join '', @{$msg};
 
        my $parsed = Email::MIME->new($message);
 
        foreach my $part ( $parsed->parts() )
        {
            my $filename = $part->filename(1);
            open FILE, '>', $filename
              or do { warn "can't open $filename - $!"; next; };
            print FILE $part->body();
            close FILE;
        }
        $popclient->delete($msgnum);   # remove if you want to keep th
+e messages    }
}
 
$popclient->quit();
[download]

/J\

POP account, apologies.