For those curious about the performance of the $5 Raspberry Pi Zero, here are some benchmarks I've just finished up for this low-end, low-power ARM development board compared to other ARM, MIPS, and x86 hardware.
The Raspberry Pi Zero launched one week ago as the foundation's cheapest board yet (just $5 USD!) and also their smallest at about half the size of a Raspberry Pi Model A+. The Raspberry Pi Zero features a 1GHz single-core ARM processor, 512MB of RAM, mini HDMI and USB OTG ports, and a 40-pin header. There isn't any onboard Ethernet so you'll need to end up using a USB-based Ethernet or WiFi adapter. The Broadcom SoC in use by the Raspberry Pi Zero is a BCM2708.