How Small Can We Go?

How small can we go with critical embedded computing elements? I know that there are microscopic embedded computers that can power drones the size of a humming bird, but when it comes to open standard, multiple module computers, how small can we make them and still be practical?

There are three small form factor initiatives under development with working groups at the VITA Standards Organization (VSO). Each of them are in the size range smaller than a 3U card and each is designed to integrate multiple modules via a serial fabric interconnect of your choice. The target markets are anywhere this size is required due to size, weight, and power (SWaP) constraints.

But do we need to go smaller for modular systems and if so how much smaller can we go with today’s technology? When do we approach the step that jumping to an SoC or FPGA with an embedded processor makes more sense? I have seen plenty of modules that are much smaller, but most do not interconnect or if they do, the interconnect is simple, such as USB, or maybe Ethernet.

I would live to hear what you have to say. Pass on any examples that you might know about.