My real first home computer, around 1976, was a perfboard with my design for an 1802 cpu, 1K of 1103 RAM chips, a video chip that did B&W blocks, a hex keyboard made of discrete switches with a two character hex display, and a bunch of support DIPS all hand wire-wrapped. There was no ROM, you had to hand load memory in hex and then start the CPU. Quickly I wrote a short loader that could load data from an audio cassette so only the loader would have to be keyed in. Earlier, around 1968, I got some kind of computer (I had never heard of the manufacturer) from a military surplus program for schools (incredible program - made a huge difference in my learning). It had a remote terminal that was like a fancy calculator connected with a thick cable to a box the size of a small refrigerator. Inside was a mass of panels and thick wire-wrapping connecting discrete transistors. Unfortunately it didn't work properly and in spite of many hours trying, I never did figure out how to fix it so it probably doesn't count although I learned a lot. Much later I got an Exidy Sorcerer with the S-100 expansion. I replaced the ROMs with custom ones I wrote and burned that included a real time interrupt so it could timeshare and multitask and load other ROM images (I could load ROMs to emulate a TRS-80, a Polymorphic 8813, and custom stuff). Later I added a Micropolis floppy drive and wrote a loader that read and compiled, starting with the first sector, forth-based text. I remember getting two floppy diskettes and wondering why I would ever need any more.