Groupon offers the Unlocked Nokia Lumia 810 Windows 8 Smartphone for $310 with free shipping. That's the second lowest total price we've seen for the unlocked version of this phone, although we saw it for $30 less two weeks ago. (For further comparison, we mentioned a refurb for T-Mobile for $240 shipped a month ago.) This quad-band UMTS phone features a Qualcomm Snapdragon S4 1.5GHz dual-core processor, 4.3" 480x800 Nokia ClearBlack OLED touchscreen display, 8-megapixel rear-facing camera with dual-LED flash, 1.2-megapixel front-facing camera, 1080p HD video capture, 8GB internal memory, WiFi, and Windows 8 OS. Deal ends May 22.