Marvin’s birthday cake:
based on Marvin’s book:
and created by these folks.
I think they did an amazing job.
I suggested the “zero to infinity” since it’s what you get if you turn “80” sideways. I had in mind a “zero” over the “lazy” eight, $0 \atop \infty$, but I think it’s more readable as it was translated through two phone calls into the image above.