Dwarfputers are a wonderful tangent of their own, with a not-unlikely possibility of flooding your entire computer with firey death in the form of magma in some of the more impressive approaches - this has been possible (but quite difficult) for some time, more recent game versions have made non-fluid based logic gates[1] more realistic and usable.

Someone has built an (admittedly simple) space-invaders game[2] using df which is rather impressive.

1. http://dwarffortresswiki.org/index.php/DF2014:Computing#Disc...

2. https://www.youtube.com/watch?v=j2cMHwo3nAU