Hey, thanks for the info. I think that could be a pretty good idea for the winter, here, but I wouldn't use one in the spring and summer months.

I think that a filter like that could be pretty useful here in france. Over 50% of cars are now diesel and the fumes are much dirtier than gas engines. The worst was when I was passed by a slow moving cement truck, and then a military truck and bus. They really pipe out the soot!