Cowboom offers the used Sony Upscaling DVD Player, model no. DVP-SR500H, for $4.99 plus $5.99 for shipping. That's the lowest total price we've seen for this player and $18 under the best price we could find for a refurb. Sales tax is added where applicable. It features upconverting to 1080p, PhotoTV HD mode, Precision Cinema Progressive for cleaning up artifacts in the background of movies, and an HDMI port.
Note that no warranty information is provided. Also, these used items may have cosmetic blemishes and/or be missing accessories. (Most don't have the remote or cables.)