Now winter is on its way many of us will be using our equipment less. 

But how much thought do you give to the way you store your equipment? Not much? Well you should!

Inappropriate storage can encourage the development of fungus and mildew. Once established this is very difficult to clean (it eats into and etches lens and sensor coatings) and can decimate the value of equipment. 
Fungal spores thrive in dark and airless environments. Any humidity will encourage growth on organic material such as leather, cotton (e.g. cases, straps etc) and, surprisingly, optical coatings (yes, the coatings on lenses, prisms, rangefinders and sensors).
In summary, consider the following: 

✔  Ventilation✖  Airless cases, drawers etc
✔  Low humidity✖  Damp, humidity
✔  Sunlight / UV radiation✖  Darkness

If you store equipment in cases or bags then sachets of silica gel will reduce humidity but remember it'll become saturated and must be dried out regularly. Cupboards are generally better with humidity kept under control with rechargeable mini dehumidifiers (we use Amcor MD100s which can be bought for around £30).
However, the best form of prevention is use. Regular visits outside into the fresh air and sunshine will ensure unwelcome fungal spores don't enjoy an environment that'll encourage their development.