The "Prouino" Is designed to be a cost effective development board with WiFi connectivity. It combines an ESP8266 with an Mega328 for considerable computing power in a 36x36mm PCB. The blank PCB in the picture is powered via a LioN Polymer battery, which is rechargeable on the PCB via USB (mini-B). Many development boards stress an increase in GPIO pins. I decided to take a different route and included a 3.3v and GND rail with six connections. I did for many reasons, but mainly because I wanted to experiment setting CH_PD and other pins on the ESP8266 High/Low. This version has 5 of the GPIOs of the Atmel chip and 3 of the pins of the ESP8266 available for prototyping. Firmware can be loaded via ISP pins, and hopefully in the future, online via the ESP8266. There are two microcontrollers for multiple reasons, but mainly because the ADC on the ESP8266 only handles 0-1V. Battery management is handled via a Microchip MCP73831.
I had to put it in the Solder Oven twice, and it took some work afterwords with the hot air gun, but I was able to get all necessary components soldered on the Prouino (remind me never to go lower than an 0805 package again). Just need to run it under the microscope to make sure there are no issues.
One of the reasons I am excited about the Prouino is because it will come with a LiPo battery attached, and will be rechargeable via USB cable.
For those wondering, the circuit board measures 36x36mm.