I'm in the process of designing a small PIC board that I can stick a number of different footprints on to take a range of devices. I was going to allow flexibility for plug in expansion (like the Arduino shield) but still keeping it small and simple, and being compatible with breadboards. The plan was to use it on the UAV and a couple projects for my motorbike.
I wasn't happy with the cost of the Arduino. It's too big and expensive to leave in many simple projects (especially if using shields). The smaller versions have no on board USB, which means more faffing. There is a slightly bigger version that does have USB on board, but that's only a few £ less than an mBed and doesn't do USB host, CAN or Ethernet (unless I'm mistaken).
So I'm going to simplify my PIC board, for simpler projects, keep it smaller and cheap (10+ for the price of an mBed?). When I need USB/Ethernet/CAN, I'll use an mBed.
