I got Black Tooth laser CNC machine from buildyourcnc.com. I came with a parallel BoB. I used it with LinuxCNC, the laser on/off was on Z direction pin. this made the software toolchain complex. So I replaced it with GRBL and life is now simple.
When the first Raspberry Pi, it was very exciting time. So I designed a PCB for RPi with arduino connectors and power supply section. I ordered 10 on them. After soldering the headers and stuff I tried mounting on the Rpi. Turns out I got the profile of the PCB wrong around the video connector. Here is the failed pcb.
The arduino headers were good. So I figured I'd use this as an Arduino shield and solder screw terminals on proto area.