PassagePlus

PassagePlus is a passage planning, navigation and ship tracking application aimed at the leisure sailing market.

It is intended primarily for the day/weekend coastal sailor, but will also be of interest to the ship-spotting enthusiast thanks to its extensive AIS capabilities. It works with the UK Hydrographic Office's ARCS charts, Land Information New Zealand's NZMariner charts and the Australian Hydrographic Service's Seafarer RNC charts.
It has an uncluttered interface usable on a small laptop like a MacBook Air and a feature set restricted to those things that might be used frequently by this kind of user.