I etched the PCB using a slightly modified version of Raijuu's Ycard header as i downloaded it sometime ago.
Raijuu's version appealed to me as it is an easy to etch basic single sided design which will free up my Duemilanove for more important projects.
Although you can supply it with power through the DC jack socket from a Wall Wart it has to be a switched mode 5VDC type as there is no voltage regulation at all! it is mealy there for convenience.I guess i will add voltage regulation some time soon when i find out just how useful it is.
The jumper is used to select between running on external power from the front header pins and providing power to the serial programmer when programming the ATMega.
You can grab the Eagle design files including the Paper silk screen in the files section