May sound silly, but I wonder if it's done? In my thinking of the
'cruise' I'd like to get out of hte idea of coolers packed with frozen
water. I know that small friges are available but I dont' really have
the space for that on my boat. The 12.v reefers can pull a lot of
current which I can make the power easily enough, but they ARE
expensive! then there's the cheap 120 v ones which can use I can use
an inverter to run, but they don't cool quickly and seem to run a lot
for no more benefit then I think I'd get. Then theres the refrigerated
coolers that run off a cigarette lighter socket but they only cool
down a little less than the outside temp which isn't much.

Drawbacks? Finding a container that would hold it without cracking,
and regulating the evaporating rate to get some kind of consistant
temperature. And it's volitile as far as handling it goes. "instant
frost bite" if it contacts skin. But I've worked with it in the past
and tongs work great for it. One advantage is that it evaporates to
nothing leaving only condensed humidity behind.

There is a local company that uses dry ice and they sell it resonably.
So instead of having sadwich material floating around in ice water, I
thought though far fetched, this might be a decent idea.

But I also realize that if it could be done easily, then everybody
would be using it.

Besides saying "forget it!" Anyone have any ideas about it or know of
a website that tells about how it can be done?