Way back in the early days of computers (that’d be 1936 to be exact), Alan Turing described a machine in a thought experiment. This hypothetical machine would have an infinitely long tape upon which it could write (and from which it could read) symbols. His paper showed that such a machine with the correct minimal set of operations could calculate anything that is computable.
Mike Davey decided he’d like to build an actual Turing machine. Of course, he couldn’t use an infinitely long tape — but 1000 feet of white film leader and a dry erase marker do the job pretty well:
This video is impressive, but only gives you a quick overview of the machine and its components. If you find this at all interesting, you’ll definitely want to check out the website that Mike put up to document his creation.