LightInTheBox offers the Xiaomi Mi Box 8GB Android TV Streaming Media Player for $56.48 with free shipping. (Select the "US Adapter option.) That's tied with our April mention and the lowest price we've seen. (It's the best deal now by $13.) It's powered by Google Cast (with access to Netflix, Hulu Plus, YouTube, more) and features 4K support, 2GB RAM, 8GB internal storage, 802.11ac wireless, and a Bluetooth voice remote control.
Note: This item ships from China and may take three to four weeks to arrive. Uncheck "Add Shipping Insurance to your order" during checkout to remove the 99-cent fee; additionally, you may need to select the free shipping option.