Guess I win this round, unless there are older farts than me - Commodore VIC-20 with 3.5KB RAM which was plenty for me to do really cool things with in BASIC and 6502 machine language)
It predated the VIC-20 by just under 3 years. You might have had 3.5KB free for BASIC programs but the VIC-20 had a comparatively spacious 5KB of RAM and 20KB of ROM.