Is there such a product out there that could easily be mounted to a window
to send in a constant flow of fresh air?

This would be great for cold areas like here where its not a great energy
saver to open the windows when its always 10 degrees in the winter.

Im thinking of a device that filters (hepa filter) the air and warms the
temperature of the air to room temperature and then flows it indoors.

I have alot of allergies / chronic headaches and crap like that. If I dont
open the windows once every 3 days the stagnant air builds up and I feel
like crap again. Once I get fresh air in again I feel much better.

Im not even sure if such a product has even been invented yet? If not,
someone might be able to get rich trying.

John