A bulb was also a neat hack used in the 200A, the first product made by a small and relatively obscure garage startup in Palo Alto: https://en.m.wikipedia.org/w

A bulb was also a neat hack used in the 200A, the first product made by a small and relatively obscure garage startup in Palo Alto: https://en.m.wikipedia.org/wiki/HP200A https://en.m.wikipedia.org/wiki/HP200A