If you want to write as few lines as possible, you might try:

#!/usr/bin/perl

use strict;
use warnings;

use Date::Calc qw(Delta_DHMS Time_to_Date);

my @secs = qw(1000 10000 100000 1000000 86400 86399 3600 3599 0 31394 
+2941 -2941 -86399);

for (@secs) {
  printf("%s%02d:%02d:%02d:%02d\n", $_ < 0 ? '-' : '', Delta_DHMS(Time
+_to_Date(0), Time_to_Date(abs($_))));
}
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Quick 'n' easy, and negative "time remaining" will still print out nicely.

Edit: Or, as a subroutine:

sub time_remaining {
  my $input_seconds = shift;
  return sprintf(("%s%02d:%02d:%02d:%02d", $input_seconds < 0 ? '-' : 
+'', Delta_DHMS(Time_to_Date(0), Time_to_Date(abs($input_seconds))));
}
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