AI6YR BenTrying to deal with wildfire smoke? Here's the best thing since sliced bread for massively improving the air quality in your room/apartment/house/etc.
How to build your own Corsi-Rosenthal Box
Stephen Dioxide 
@ai6yr This is my cue to observe that you can scale this up by taping the filter over a window or two, and then placing a fan facing out in the farthest window in the house. I've done this two summers in a row.