Thanko Armpit Cooling Fan — Japanese company Thanko is a compact battery-powered fan that clips to shirt sleeves to keep its user cool in the hot summer months. The fan has three settings, rechargeable batteries, and can help get cooler air to sweaty areas that would be otherwise unventilated.
Thanko Armpit Cooling Fan Overview:
Two AAA batteries will keep the fan blowing for five to nine hours, depending on which of the three selectable speeds you use. Alternatively, you can power the device by plugging the included 35-centimeter (13.8-inch) USB cord into your PC or a separately purchased battery pack.
The Armpit Cooling Device is priced at 1,980 yen (US$19) for a single unit, or 3,800 for a set of two (domestic single orders here, two-unit set orders here). The clip-on design means that in addition to attaching the device to your sleeves, you can also use it to keep you stomach or neck cool by positioning one on the front or collar of your shirt.