A retired UK man known only as "Mike" has built a working computer inside his spare room using 460 recycled Soviet-era vacuum tubes, documenting the project on his own website and Hackaday. The build is notable because each 6N3P tube, originally rated for about 500 hours of life, had already been used and stored for over 50 years, forcing Mike to design and test custom component values rather than rely on textbook specifications. It represents an extreme hobbyist take on retro computing, going far beyond restoring old consoles or 1980s PCs.

The finished machine contains 920 thermionic triodes across 46 ten-tube circuit boards mounted on five backplanes, uses NOR logic gates similar to the Apollo guidance computer, and can perform 16-bit maths via a 4-bit instruction set. It takes 10 to 15 minutes to stabilise after power-up, warming the whole room in the process, and currently outputs a 64-bit Fibonacci sequence via a repurposed British Rail station clock display. Mike, who calls tube computing "an addiction" and has now built three such machines since 2021, plans to finish its input/output system so it can run a simple flight simulator based on a 1920s airship voyage from Brighton to Paris.