Re: Mini computer
It's orders of magnitude faster than any old minicomputer. While Wikipedia is vague about what last qualifies, it does say that the term was last really used in the mid-to-late 1980s. The IBM AS/400 would be a good comparison, but Wikipedia also lacks specs on it for some reason. However, it does say that the CPU used was clocked at 22 mHz. Even the lowest-end Pi outstrips that clock rate significantly (Raspberry Pi Zero at 1000 mHz), and although the architecture means the rates aren't directly proportional, that means at least twenty times faster. Memory speed and size are also significantly larger.
I did find sufficient specs to compare the Pi against a different computer of the era, although it's not quite a mini. It's the Cray X-MP from 1988. That was more a supercomputer than a mini, but even it lags behind that lowest-end of Pis. That's on all aspects--CPU performance, memory speed and quantity, storage speed and quantity, to say nothing of the multimillions price of one and $5 price of the other. Now add in the fact that the newest Pi out there has four cores at 1.5 GHz and 8 GB of memory. It's amazing how well such things have improved in the last three decades.