The ODROID-C1 quad-core single-board computer is now available, and it's only $35.
Like Raspberry Pi, the ODROID-C1 is a credit card-sized single-board computer, but despite the similar price point, it's much more powerful. Short for Open + Android, the ODROID-C1 boasts a 1.5GHz quad-core ARM processor and is capable of running Ubuntu Linux 14.04 or Android KitKat. The board has 1GB of DDR3 RAM.
Despite its small size, the ODRIOD-C1 features a bevy of ports and slots. It has four USB 2.0 ports, a micro-HDMI port, RJ45 Ethernet, a row of GPIO (general purpose input/output) pins, a MicroSD slot, micro-USB connector, Infrared (IR) receiver, and an eMMC module socket, which offers storage access two to three times faster than via the SD card.
With all this packed into a single board, all you need is a monitor, keyboard, mouse, and power to have a fully functioning super-tiny system. Unfortunately it can't run SteamOS, since Valve's version of Linux currently only supports x86 processors. The ODROID-C1 can't handle game streaming, then, but it could be a mega-cheap living room client for a media streaming setup with something like Plex installed. Or you could build your very own Android-based Ouya alternative. Or if you just want to tinker and learn your way around Linux and PC hardware, it's hard to do it cheaper than $35.