Software

CelestNav
Palm Pilot shareware for finding your geographic position with a sextant.
http://www.mobilegeographics.com/celestnav/

GeoMagneticInfo
A Palm Pilot application to compute the magnetic declination, inclination, and magnitude for any location on Earth.
http://www.40-below.com/palm/geomaginfo.html

Navigator Software
Celestial and chart navigation software. Star finder. Nautical Almanac.
http://www.tecepe.com.br/nav/

NavStation
Pocket PC software for leisure vessels, including logbook, passage planning, tidal prediction with interfaces to GPS and other NMEA or SeaTalk devices.
http://www.navstation.co.uk/