Good Guys Electronics via Amazon offers the Unlocked Nokia Lumia 520 Windows Phone 8 Smartphone in Black for $99.99 with free shipping. That's $5 under our mention from two days ago and the lowest total price we've seen for the unlocked version of this phone. (It's a current low by $5.) Features include a 4" 480x800 touchscreen IPS LCD, Qualcomm Snapdragon 1GHz dual-core processor, 8GB internal storage, WiFi, Bluetooth, microSD card slot (up to 64GB), and Windows Phone 8 OS.
Update: The price has dropped to $98.99.
Update 2: The price has increased to $99.99 with free shipping.
zte_us via eBay offers the Unlocked ZTE Open 256MB Firefox OS Smartphone in Orange for $69.99 with free shipping. (Multi-Function1002 via eBay charges the same.) That's $10 under our September mention and the lowest total price we could find by $29. It features a 3.5" 320x480 touchscreen display, 1GHz Cortex-A5 processor, 256MB RAM, 512MB memory, 2-megapixel rear camera, accelerometer, Bluetooth 2.1, WiFi, and Firefox OS.