The GPS Broke. Now What?

I'm not going to fall into a Luddite rant about the evils of electronics; it's so easy to simply plug in a GPS waypoint and steer to it that even I occasionally leave my sextant and tables at home when I go on deliveries. But I also always keep an updated "estimated position" that tells me where I am and what course I should be steering to make my next waypoint. Practicing some of the more traditional forms of coastal navigation is a good mental exercise, and personally, it makes me feel like quite the old salt when I haul out the hand-bearing compass.