Rui Carmo
My first computer was a ZX81 (which lasted me many years) and pretty much the entirety of my career stemmed from that, even though it took me years to fully appreciate the genius and thriftiness of its design (as well as the Spectrum’s, which I used until I got my first 286 PC for college), or the care that was put into the manuals it shipped with (which were arguably the best computing tutorials for regular people ever written).
It is a great thing that we have machines like the Raspberry Pi to approximate that sense of wonder and exploration for our kids, but sometimes I wish we placed the same emphasis on making computers understandable from basic principles.