Micro Center offers the Acer 27" S277HK 4K Ultra HD IPS LED-Backlit LCD Monitor
. Opt for in-store pickup
to dodge the $17.10 shipping fee. That's the lowest price we could find by $20 and the best deal we've seen. (For further comparison, most vendors charge $440 or more.) It features a 3840x2160 (4K) native resolution, LED backlight, built-in speakers, and HDMI, DVI, and DisplayPort inputs.