Just wanted to share a project with the forum.
Like other musicians, I have a few keyboards and sound modules that use the older (but not obsolete!) 5-pin DIN MIDI connectors. I want to use the littleBits Arduino module as a MIDI controller, sequencer and tone generator with this gear. In order to get started, I built a 5-pin MIDI interface and connected it to a littleBits Arduino module using two proto modules. I also tried the littleBits Arduino with a Sparkfun MIDI breakout board.
If you would like to read about the design and testing of the MIDI interface, please check out the links below. The pages have a few sketches that you might find helpful.
Thanks for sharing all of your ideas here!