How to Build a Cheap Air Purifier
by Beth Skwarecki on Vitals, shared by Beth Skwarecki from Lifehacker on (#439AS)
A high-quality HEPA air purifier can eliminate nearly all the smoke, dust or allergen particles from the air in a room-but a $30 contraption can eliminate about 90 percent. It's worth a try if you need to clean your indoor air on the cheap.