DeviceGuru writes: Curious about the low-cost Amazon Kindle Fire Android tablet? If you’re quick, you might be able to snag a refurbished unit for $139 at Amazon. The company introduced the Fire at the end of 2011 at the loss-leader price point of $199, though it’s rumored to cost around $210 to build. So at $139, you’d be getting the Android-powered tablet well below cost. Step one: buy refurbed Kindle Fire. Step two: root it and enjoy!