VMInnovations via eBay offers the Cool Living 4-Stage Air Purifier for $47.99 with free shipping. That's the lowest price we could find by $2. It features a HEPA filter, remote control, and up to 690 square feet of coverage.
Want to save a few more pennies? You can score it for $47.49 by applying coupon code "WEVALUEYOU" at VMInnovations direct.