Roland PMA-5

images via this auction. There is also one here.
via brian c:
"I have one and I use it all the time it as a kind of musical "leatherman" for testing MIDI related devices, or ideas .......I've also taken it with me on Craigslist purchases so I can check stuff out before I hand out the cash....although I haven't bought much in the last year....just a T-resonator ...I don't really use it for music making much, but sometimes when I travel I throw it in the suitcase as a sound module for the laptop. .....the canned sequences, tacky as they are, are also good for for trying out chord sequences because you can chain chords together within the sequencer and get an idea what it might sound like with better equipment, more space and more time. it has 16 channels so when I need a GM MIDI sound source it is a whole lot better than the built in one from microsoft woindows.. it does eat batteries however, so I carry a power adapter when I can. The LCD is barely readable in certain light conditions too"