Crazy. I was just thinking about doing this in my place a few months ago. I was going to actually build a little container that fit in a window and have a HEPA

Crazy. I was just thinking about doing this in my place a few months ago. I was going to actually build a little container that fit in a window and have a HEPA filter from McMaster-Carr (or wherever) sitting behind computer tower cooling fans, as these fans are designed to be quiet and low-power. This design has a ready-made chassis, though.