After taking the customary bow of respect at the person who designed this level on LBP, I’d just like to say that this was not that difficult to do – albeit very time consuming.
He did not actually design a complete computer but focused on the main computational component – the arithmetic unit. In this particular case, the arithmetic unit can perform two functions – addition and subtraction.
What this video actually shows is the exemplification of the Church-Turing thesis. In this case, the PS3 has successfully performed a simulation of an arithmetic unit, within the confines of a simulated virtual world. Nice recursion.
Also, it might seem weird that this computer was constructed from moving parts instead of, say, electrons. However, before we were inundated with the world of electronic digital computers like today, we were once using mechanical computers too, such as the Zuse Z1 currently on display in Berlin. Our history of computing is filled with all kinds of computers.
Now, if only it could be turned into a really interesting gaming level.