CPO via eBay offers the refurbished Porter-Cable 6-Gallon 150-PSI Oil-Free Pancake Air Compressor for $79. Apply coupon code "P20MEMDAY" and check out via PayPal for a final price of $63.20. With free shipping, that's $26 under the lowest price we could find for a new one, although we saw a refurb for $7 less in September. It weighs 34 lbs. and features a low-amp 120-volt motor and two air couplers to support two users. Deal ends May 29.
Note: A 1-year Porter Cable warranty applies. Also, this coupon can only be used once per PayPal account within a single transaction.