I made the design in illustrator and silkscreened onto the copper, then etched it with hydrogen peroxied and muriatic acid. It is for a general purpose monophonic synthesizer, so it has a socket for the atmega, all of the unused pins (17 ) brought out to two headers, a socket for an 8 pin 12 bit DAC (MCP4921) connected to the mega via SPI and a simple RC lowpass filter for the dac's output. I'm going to solder the first one up tonight!

If anyone wants to use it, please feel free. This is the component view, so flip it for the copper side.