Another interesting architecture, not sure if it quite fits your question: the orthogonal
computer. You could think of that as vector processor with serial arithmetic -- a cross
of a Cray-1 and a PDP-8/S :-) It was invented in the 1960s by William Shooman, and sold
for a time by Sanders Associates. The Goodyear STARAN is somewhat different but inspired
by that machine.
paul