I've been looking for a good dehumidifier and I notice that each big
box store only really carries one brand and there really isn't much
online as far as reviews. I know some dehumidifiers are energy hogs...

Thermastor makes the most efficient dehumidifier, according to Energy Star.
Costs a lot but can pay for itself in energy savings. When I bought mine,
it was twice as efficient as the models sold at Sears. I use it to dry out
my swamp of a basement. It's somewhat noisy, but apart from that I have no
complaints.

http://www.thermastor.com/Santa-Fe/

The powered vent that Nick recommends would be a lot cheaper to buy and to
run, assuming it can be used in your application.

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Bill McFadden http://www.rdrop.com/users/billmc
CAUTION: Don't look into laser beam with remaining eye.