An interesting fact of ENIAC is, although it was originally programmed by plugboards in 1946, it was soon retrofitted to a stored-program computer in 1948 to simplify programming, using its spare function table units as ROM, and its extra accumulators as a program counter and a pointer. I wonder if there's any project to recreate an ENIAC simulation in stored-program mode.

For anyone interested in this period, there's a book on the stored-program ENIAC: http://eniacinaction.com/