Back in the day I purchased an Ohio Scientific Challenger 1P, that has BASIC in ROM (8K) and 4K dynamic RAM, expandable to 8K on board (which I never did, memory was too expensive). It sported a built-in keyboard.
Incredible what you could do with 4K RAM (3327 bytes free, reads upon power up) both in BASIC and 6502 assembler. I eventually stepped up to an Apple II, and the rest is history.
For some reason I still keep it.