Sphere 6800 in mid-1975. Imsai 8080 that fall. Followed by Polymorphic systems, TRS CoCo, Tandy 2000, XT286-Clone, 486-50 tower (later upgraded to AMD 586/133Mhz MB) which was just retired in favor of a 950Mhz Athlon system.
First computer programmed was GE-635 in 1966. Along the way, I have programmed for the IBM 1620, 8080, Z-80, 6800, 6809, 68000, 8086, 80286, NS32000, Fairchild Clipper, 80386, 80486, and many others.