On Wed, 1 Oct 2008 20:11:55 -0700 (PDT), Two meter troll
wrote:

I haven't seen better yet - at least not for big boat navigation with
a dry space to work and ample power. * I have no interest in
navigating on an iPod or anything similar.

I trust my GPS and electronic charts about as far as i can throw an
oil tanker.

I would respectfully suggest that you may need better equipment.
Unless you are privy to a military quality inertial system, there is
nothing else better that I'm aware of.