I had one of those, also had a "build your own microcomputer" one from the mid 1980s. It had 8 LEDs for addressing (all in binary), a single digit display (hexadecimal), 16 keys, and you had to program it in machine code.
Ahh, here it is
More info:
http://vintagecomputer.livejournal.com/67414.html
It was pretty clumsy and a bit flimsy. I remember cutting up the cardboard backing and soldering everything together a couple of years later.