Crusty - I know what you mean about level shifters. I use some from Adafruit that are easy to use (http://www.adafruit.com/products/757). That's a good idea to add some in, but we won't be able to for this version.
I see that now, but what I was getting at, was to free up (in the example in the article) the A4/A5 pins... so they are connected to the shield, but free on the Mega for other use. I guess we're talking about a 3-way switch equivalent, almost, since you already have seperate jumpers inside the board outline.
BTW, Big fan, Duane - I purchased several things from you in the past (Ham Radio related items).
Sergeant82d - If I understand what you are asking correctly, we do have such a double row of jumpers. They are just on the inside of the standard header blocks. The jumpers allow the screw-terminals to connect directly to the Arduino pins, or be kept separate and used in the proto area.
Max, why not make the board a bit wider (.4 inches, MoL), and put in a double row of pin headers between the board connectors and the screw connectors on each side? Then you can either jump or open the block connectors and still have all pins available. Just a thought.
It really is a funny old world. It was probably only a year or so ago that I first heard of Kickstarter. I thought "that's a great idea," and I've supported a few interesting projects here and there, but I never really thought of doing one myself.
Then, a month or so ago, I saw a screw-block prototyping shield for an Arduino Uno, and I thought "that would make my life so much easier for my projects" -- but no one makes one for the Arduino Mega.
So I called up my chum Duane, who lives at the other side of the country, and explained what I was looking for. Duane also plays with the Arduino, and he agreed this would be jolly useful, so we bounced ideas back and forth and came up with what I think is a rather cunning implementation (especially with regard to the way you can link header pins to their screw-block counterparts, or you can insert circuitry between them if you wish).
So Duane designed the prototypes while I blogged about them. The funny thing was that we received so many emails from people wanting to get their hands on these proto-shields that Duane said "What about doing this as a Kickstarter project, because if we get enough people interested we can make these much more cheaply" ... and so that's what we're going to do.
Watch this space for future blogs on this topic...