Groupon offers the Samsung 40" 4K 2160p LED-Backlit LCD Smart Ultra HD Television, model no. UN40HU7000, for $579.99. Coupon code "GOODS5" cuts it to $550.99. With free shipping, that's $49 under last month's mention, $649 off list, and the lowest total price we could find. It features a native resolution of 3840x2160 - four times that of 1080p TVs, LED backlight, WiFi, Smart TV apps (YouTube, Netflix, Hulu, etc.), USB, and four HDMI inputs. Deal ends June 25.