That Beagle Board suggested in post #8 looks interesting. It's very much a hobbyist device, though, despite sharing the same processor
core as the
current crop of iThings. If tinkering (and rewriting code to suit the ARM core) is your thing, it might be interesting to play with....
Netbooks may look appealing at times, but personally, I find any
monitor less than 19" to be a bit cramped- a 10" netbook is four times too small a
screen, IMHO. Add the driver issues that plague many of them and the fact that they're a pain to
repair. But Atom motherboards are
cheap and plentiful (an Atom N230/Ion board with all the usual
ports is about $160). Add a big stick of memory, a small solid-state drive (or use a CF card) and you should have a system that would run
OpenCPN on twenty, perhaps thirty watts (plus whatever your monitor draws) for perhaps four or five hundred bucks. The Atom also has the distinct advantage of not requiring you to recompile any of your apps or your OS (Gentoo
Linux nuts excepted, of course).
The real thorny issue for low-power onboard
computers, IMHO, is not the processor but rather the power supply. Losing 10% in the
inverter, then another 30% in a normal
desktop PSU, sucks. More efficient
desktop and server PSUs (80% +) seem to be mainly in the 400+ watt class. If anyone has found a decent +12V to ATX power supply, that would be great- the thought of hacking together a custom one out of DC/DC converters is not appealing.