The Raspberry Pi Foundation announced a new super low price device yesterday - Rasperry Pi Zero and mine arrived today. I didn't manage to find a copy of the magazine where this was included as a free cover computer!
This needs a micro SD card, a micro usb power adapter capable of providing 160mA and a mini-HDMI plug if you want to connect this to a TV. I intend to use this headless and just hook up a serial console but it seemed sensible to initially start it up with a display.
The SD card I obtained as part of the kit from PiHut had NOOBS setup so this needed selecting using a USB keyboard and the HDMI display and then it went and installed Raspbian for me. To just use a serial console would require installing Raspbian on the card before powering up the Raspberry Pi.
Once the initial boot was complete I connected a USB TTL serial adapter to pins 6, 8 and 10 (GND, TXD, RXD) and started a serial monitor to get logged in. screen /dev/ttyUSB0 115200 and it's up and working. Handilly the serial pins are all on the opposite side from the I2C pins I need to use for a DS3231 real time clock chip so I can attach that to give it an idea of the correct time as well.
Time to hook it up to a robot.