Here's a genius idea for a quick do-it-yourself air purifier! All you need is a filter and a fan! If you have seasonal allergies etc. this will help a ton.
Just face the filter with the arrow pointing towards the fan saying "Air Flow" and it will cling to the fan on its own.
Depending on your fan size will depend on what size air filter to buy but you can just buy the cheap allergen ones on sale!