I had a problem with my Arai shield fog'n up in the cold up in AK... so I got a Fog city insert... it's one of those photochromatic ones... goes from a light green (like a car window) to a dark blue in about 3-5sec... works great! can't fog the fuck'n thing up no matter how hard I try... and it's dark enough to ride in even the brightest of light... but clear enough to ride at night with.
you can see it on my helmet here
