When you share an office with another, whether it's your home office or in a work office, chances are the AC is either too cold or too hot for one person. Sometimes a desk fan can offer some level of comfort for hotter temps without going to to the extreme of a cold blasting AC, especially in spring and early summer...
Dyson Desk Fan
The fan, called the Dyson Air Multiplier fan, does away with the blades used in common desk fans. Instead, the Air Multiplier uses a loop whose cross-section is shaped like an airplane wing to funnel air towards the user. Air is pulled in through tiny holes in the fan's pedestal, and pushed out through a narrow slit that runs the circumference of the loop. By utilizing the wing shape instead of a number of fan blades, the Air Multiplier generates a gentler, smoother breeze. The fan comes in two models, a 10-inch version that will retail for $300, and a 12-inch model that will go for $330.
Mini Cooling Fan
This fan does it with out propellers aiming at your face. We love that the form factor makes it less intrusive when placing on the top of a desk and the fact that you can direct the breeze using the adjustable vent is a plus. The only problem is that it looks too much toy-like and maybe you will only get a tiny amount of wind towards your face.
Solar Powered Desk Fan
This is something perfect if you are after the DIY look. Made out of perspex and using the power of a solar panel, it can harvest, even the tiniest amount of light into power to produce a cool breeze and keep you cool. We love that comes in the form of a kit that you put together yourself with instructions included. Of course, placement is key to keep the fan going, so unless you have a window office, with direct sunlight, you won't get too much action with this one.
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I love those Dyson fans, but OMG could they be any more expensive?
In some regions, it's not just about keeping cool, it's also about controlling humidity. Here in the South, and especially in the Deep South, it's just as humid in the spring and early summer as it is in the late summer. Fans are just going to blow around that hot moist air, and that isn't going to help because your body's evaporative cooling (i.e. sweat) doesn't work when the humidity is too high. A/C takes the humidity out of the air, and allows your body's natural evaporative cooling system to work.
That's also why swamp coolers are badly named; swamps tend to be humid, and evaporative cooling just won't work in high humidity.
One might say, "well, just run a dehumidifier instead of that high-powered A/C." Dehumidifiers are simply air conditioners without fans or blowers. They use the refrigeration system to condense the moisture in the air, but don't have the fans to circulate the air. So you don't save much in the way of power usage. Then you add fans all over the house to circulate the air, so you might as well use the A/C.
Oh, and here's a dirty little secret: that Dyson Air Multiplier? It has a normal bladed fan in the base.