Even with the hatches open, or on those sticky, rainy nights, in warm weather, not all the bunks on your boat are going to get a nice cooling breeze unless you have a fan pointing at them. Caframo's Sirocco cabin fan is a quiet, compact device that puts out a ton of breeze. The motor only draws .4 amps and the fan shuts off completely if the battery voltage drops below a certain voltage. It's available for 12- and 24-volt systems.
$100 (12-volt model), (519) 534-1080, www.caframo.com