And here's a shorter 'bigdivide'.

sub bigdivide
  {
  my ($t, $d) = map s/^0+(?=.)//r, @_;
  my $q = 0;
  $d .= 0 x (my $zeros = length($t) - length $d);
  for ( 0 .. $zeros )
    {
    $q .= 0;
    while( defined( my $try = bigsubtract( $t, $d ) ) )
      {
      $t = $try;
      $q++;
      }
    chop $d;
    }
  return ($q || 0) =~ s/^0+(?=.)//r;
  }
[download]

UPDATE: Should be 'defined' in the while :(