Palm keyboards are special keyboards that fold up in to compact box. These keyboards communicate with palm via RS232. Hard to say if they are still in production, but probably you can find one in your loft.

Palm keyboards use non standard RS232 connector, so PIC based Morse code application uses a fabricated socket. Application itself is simple - it beeps Morse code depending on key is pressed. Application is written in ASM language for 16f628a microcontroller.