It doesn't get more versatile than this. The ASUS Transformer Book Duet doesn't just double as a 13-inch laptop and a tablet. This detachable runs both Windows 8.1 and Android. With the push of a button, the Duet switches from OS to the other in about 4 seconds. Having this kind of choice gives shoppers the best of both worlds: the ability to get real work done in Windows and then kick back in Android mode for enjoying more apps and games on the full HD IPS screen. The starting $599 configuration has a Core i3 processor, but you can step all the way up a Core i7 CPU, 256GB of solid state storage in the tablet and an extra 1TB of space in the keyboard dock.