I wrote a scoring program on my TI-84 calculator, so you can calculate your score right at the field. It is much easier to carry around than a laptop. It includes both the autonomous and operator periods.
I hope it can work on some of the older TI calculators, but I haven't been able to test that yet.
The program can be found here:
http://drivenrobotics.com/ under "downloads"
Caleb Swieson
Member of DRIVEN Robotics Teams 2073 and 2158