If you think you will be doing all of your waypoints and navigation on your
laptop, you might consider using a GPS module. It is about half the size of
a pack of cigarettes, doesn't require a external antenna (unless your boat
has a metal cabin top). I use one and just double-back-tape it to the
overhead over the nav station.

Here is a eBay listing that give all the specs.
http://cgi.ebay.com/ws/eBayISAPI.dll...ategory=46 68

I still have a couple old Apelco handhelds but have found I seldom ever use
them.. The only time I find them useful is when I want to watch my progress
in the open sun of the cockpit where the laptop would 'wash out'.


--
My opinion and experience. FWIW

Steve
s/v Good Intentions