[BarbaryCoast]

Look at the earliest computers, that is, those around the time of ENIAC. Most were electro-mechanical, some were entirely relay machines. I believe EDSAC was the first _electronic_ digital computer.

As for weird, try this: ENIAC instructions modified themselves. Back then, an "instruction" (they called them "orders") included the addresses of the operands and destination (which was usually the accumulator). So if you wanted to sum the numbers in an array, you'd put the address of the first element in the instructions, and as ENIAC repeated that instruction (a specified number of times), the address in the instruction would be auto-incremented.

Or how about this: a computer with NO 'jump' or 'branch' instruction? The ATLAS-1 was a landmark of computing, having invented most of the things we take for granted now, like virtual memory, paging, and multi-programming. But it had NO instruction for altering the control flow. Instead, the programmer would simply _write_ to the program counter (PC). Then the next instruction would be fetched from the address in the PC. If the programmer wanted to return to the previous location (a "subroutine call"), they'd be obligated to save what was in the PC before overwriting it. There was no stack, unless you count a programmer writing the code to save a specific number of PC values, and adding code to all subroutines to fetch the old value and restore it to the PC. I do admire the simplicity -- want to run code at a different address? Tell me what it is and I'll just go there, no questions asked.

Or maybe these shouldn't count as "weird", because no one had yet figured out what a computer should be. There was no "standard" model (despite Von Neumann) for the design of a machine, and cost considerations plus new developments (spurred by wanting better computers) meant that the "best" design was constantly changing.

Consider that post-WWII, some materials were hard to come by. So much so that one researcher used a Slinky (yes, the toy) as a memory storage device. And had it working. They wanted acoustic delay lines (the standard of the time), but the Slinky was more available. So it did the same job, just with a different medium.

I've spent a lot of time researching these early machines, wanting to find the path each item in a now-standard model of an idealized computer. It's full of twists and turns, dead ends and unintentional invention.