The Huawei HiKey 960 is essentially a PC running Android.
At a whopping $239 it's not cheap, but it certainly has the horsepower to handle whatever task you want to throw at it.
A $135 quad-core board that's just as at home running Android as it is Linux.
Banana Pi M3 is a super charged single board computer with an Octa-core processor and 2GB of RAM. It also features Gigabit Ethernet, 2 USB, SATA, WiFi, Bluetooth, and HDMI connection. It can run on a variety of operating systems including Android, Lubuntu, Ubuntu, Debian, and Raspbian.
The easiest way to create internet-connected devices - no programming, soldering or wiring required. IFTTT support allows it to connect with any web service, like Facebook, Gmail and Twitter, or hardware like NEST and Philips HUE.
All for just $59.95.
The Parallella computer is a high performance, credit card sized computer based on the Epiphany multi-core chips from Adapteva. Starting at $99, the Parallella can be used as a standalone computer, an embedded device or as a component in a scaled out parallel server cluster.
At around $92, the Intel name doesn't come cheap, but this Arduino-compatible board is turning out to be a popular choice.
The PixelPro features a i.MX6Q Quad-core ARM Cortex-A9 running at 1.0 GHz, with 2D and 3D GPUs and an embedded 2GB 64-bit DDR3 RAM, which means that it is capable of running rich multimedia applications, embedded web servers, digital entertainment systems, industrial control systems, and high definition video.
At $129.95, the PixelPro is not cheap, but you get a lt of power for the cash.