Review on Efficient Portable Ceiling Fan: Mini USB Tent Fans for Camping, Outdoor Hanging Gazebo Tents Ceiling Canopy Fan, 5V DC Compatible, Battery Powered by Kevin Woods

I was skeptical that a USB powered fan could be powerful enough to be practical. This little guy, and he's really small, turned out to be pretty cool though. It looks cheap and a little touchy; Only time will tell if it can withstand everyday use, but so far it's been great. It draws only 4 watts and ends up being used off the grid in our screened backyard house along with some lights connected to a small solar generator (Ecoboxx 150 watt hours).