Especially in summer, you can definitely start to sweat a little under a VR headset. RedRotor RC, an American company that actually specialises in components for drones, is working on Vive N Chill for HTC Vive to keep the head nice and cool. The product consists of two tiltable fans that are supposed to prevent or minimise sweating on the forehead.
The fans are attached to the top of the HTC Vive, while the power is supplied via the free USB port. The pleasant cooling effect should not disturb the immersion, which is why the fans should work as quietly as possible. According to RedRotor RC, the maximum volume is 23 decibels. Furthermore, it will only take a minute to attach Vive N Chill. Switching on and off is also quite comfortable via a button on the middle headband.
However, it is not possible to buy Vive N Chill already. The cooling system is still a prototype at the moment, but RedRotor RC would soon like to release a Kickstarter campaign in order to finance Vive N Chill. The manufacturer is aiming for a price of around 30 US dollars. The video also shows quite well how the whole thing works.
Source: VR-World