Was working for Timex Corporation back in 1981 when myself and another senior programmer were assigned to a special project.
We had to write the first demo programs for the TS ZX-81 (Sinclair) that Timex wanted to market.
We wrote a pacman clone in 8080 Assembler. If I remember correctly, we only had 4 registers to work with ... got very tricky but we did it. Storage was to tape only ... sweated it everytime we dumped to it.
Anyways, when it went to market in the Radio Shack stores, the demo game was called "Grimm's Fairy Trails" ... the senior guy's name that I worked with was George Grimm. We had a blast working with this thing.