Groupon offers the Samsung 40" 4K 2160p LED-Backlit LCD Smart Ultra HD Television, model no. UN40HU7000, for $549.99 with free shipping. That's a buck under last month's mention, $650 off list, and the lowest total price we've seen. (It's also a very strong price for a 40" 4K HDTV in general.) 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 July 27.