So, where is
the gag ? Just don't forget, the Z1 was entirely
 mechanical, to be powered by a crank (if necercary - of course they
 prefered th electric motor :). 
 Gag?  Mechanical computers are serious stuff, Hans.  Like Danny Hillis'
 tinker-toy tic-tic-toe machine:
        
http://www.yowza.com/classiccmp/toy/tinkertoy.jpg
 ObOT: BTW, does anybody know approximately when tit-tat-toe got renamed
 tic-tac-toe?  Or is a regional thing? 
 
Don't our "Queen's English" friends (uk and au) call it "naughts
and
crosses"?