I won't be investigating this myself, but here are links to a couple of navigation programs I found referenced/recommended in a sailing blog. One is free; the other, not so much.
• Free: <http://opencpn.org> (Windows or Macintosh)
• Not-free: <http://rosepointnav.com/coastalexplorer2011/default.htm> (Windows only)
[Note that Intel Macintoshes can run real Windows at ordinary Windows speeds.]
Mark_
08:51 05 May 2011