@TomWellborn October 1968, IBM 1130, Fortran IV
My high school was the math magnet school in Los Angeles and we had an IBM 1130. Astronomy and electronics were already my thing so it was an instant fit. I worked with it every day after school. Quickly picked up APL, RPG, SL/1, LISP, then fell in love with assembly coding, which is still my favorite kind of programming.