Okay, I confess right up front, this is a bit of a spam, but I think you will forgive me when you see it. We (Original Design & Development) just launched Omnuino on Kickstarter. With all the humility and reserve this retiring Brit has in spades, I think it's a pretty cool addition to the Arduino multiverse. I'll let the picture and Kickstarter tell the story...
Thanks for the vote of confidence that I wasn't presuming too much in posting this.
All the usual Arduino pin headers are available on the PCB. Yes, a few are used for the onboard accessories (mostly shared SPI) but there are still a ton available. The handheld case has room for wiring directly to the pins but no room for a shield. The wall-mount case has room for a slim shield but is really designed to go on a wall or panel and then you can keep stacking shields back into the panel and still keep a slim profile on the front. One minor compromise though is that the central 6 pin ICSP programming header usually found on the Mega is not populated so as to make room for the LiPo battery. It is copied to the edge of the board so the ICSP is still available (or just use the normal USB) but any sheild that expects those six pins (not may do) will need a bit of hardwiring. Or, if you don't need the battery you could solder that connector on. When time allows I'll post a pin diagram on our website.
Thanks for posting that. I wouldn't say it's spammy owing to it's Arduino nature.
One point that doesn't seem to be covered is GPIO.The mega has over 50 Digital and 16 Analogue, are you using them all? or is there a header that we can hook up to?
