All4Cellular via eBay offers the Sony Tablet P 5.5" 4GB WiFi 3G Android Tablet for AT&T
in Black, model no. SGPT211US/S, for $249.99
with free shipping
. That's the lowest total price we could find by $50. It features an NVIDIA Tegra 2 1GHz dual-core processor, 5.5" 1024x480 touchscreen LCD, 1GB RAM, 16GB internal flash storage, front camera and 5-megapixel rear-facing camera, 802.11n wireless, Bluetooth 2.1+EDR, 3G connectivity (an AT&T data plan is required), Google Android 3.2 OS (Honeycomb), and more.