It's of course not relevant in the current context but still fun so I dare add that it is famous because it's so bad. It's known as "worst movie ever". It is worth watching the start and a few scenes - even if one does not have the patience for the whole thing - just for some laughs. It already starts (4 minutes in) with a scene in a hilarious airplane cockpit, which does not look like one at all (those controls..!). The zombies are really funny too.
Full movie: https://youtu.be/Ln7WF78PolA
One of the reviewers of ‘Manos’ says: “What can I say about a movie so bad that it makes Plan 9 From Outer Space look like Casablanca?”, another “I have endured a thing or two in my life: Plan 9 from outer space. Hercules against the moon men. Godzilla versus Megalon. German musical comedies from the early sixties. However, THIS was too much for me. About one hour or so into the movie, I quit.”
I am very glad I had alcohol to go with it.
"Manos" is worse to the extent slogging through it is a chore, at least without commentary to add some entertainment value.
“Starting in the late 1980s, a group led by Rob Pike and UNIX co-creators Ken Thompson and Dennis Ritchie developed Plan 9. Their motivation was two-fold: to build an operating system that would fit an increasingly distributed world, and to do so in a clean and elegant manner. The plan was not to build directly on the Unix foundation but to implement a new design from scratch. The result was named Plan 9 from Bell Labs – the name an inside joke inspired by the cult B-movie "Plan 9 from Outer Space."
Plan 9 is built around a radically different model from that of conventional operating systems. The OS is structured as a collection of loosely coupled services, which may be hosted on different machines. Another key concept in its design is that of a per-process name space: services can be mapped on to local names fixed by convention, so that programs using those services need not change if the current services are replaced by others providing the same functionality.“