I was at a Cinco de Bitcoin event and someone showed a breadboard with a very simple LCD display showing the price in real time. Toggle switches, plexi, big, old school LCD readout, and you could see the wires. It was rough looking, but to me that was it's charm.  It was just a side project and he wasn't going to move forward with it, but I would definitely buy one to have on my desk as a novelty.

Having run and advised several Kickstarter campaigns, I highly recommend it.  Primary drawback is they don't take bitcoin. Good news is you can test out your marketplace with almost no risk.  You need X # of units to go into production. Set up the campaign, post here and on Reddit, and you'll know pretty quick if you've got a hit.

I would also suggest posting here some sketches of the designs, get some feedback.  For me, this is a novelty, so I like bare wires and block LED. For serious information I just use my app.

What type of unit sales are you hoping for and at what price?