MegaMIDI
A MIDI interface utility board for projects using the Arduino Mega
Duplicates the facilities of the Sparkfun MIDI shield, but with connectors for buttons, potentiometers and MIDI connectors as I usually mount these things on the enclosure and wire them to the board.
Also has connectors for SD card reader and a small OLED display to plug into.
Basically a much cheaper alternative to the sparkfun shield, with some extra flexibility for more complex projects.
Note: GND and VDD are labelled the wrong way round on the OLED1 silk screen. Check the traces if you're unsure.