I have fond
memories of playing it on the GT-40, and if Andrew Hume
is reading this he'll remember reverse-engineering the code and
modifying it for three-play operation; I think Peter Ivanov also
implemented reverse gravity...
Oops; reverse gravity (for the Sun) was implemented
for Space Wars (or
whatever it was called; this was ~40 years ago, so don't expect my memory
to be the best).
I wonder how many GT40 Spacewar implementations there were?
I have seen two: one from MIT, the other from Stanford.