We were pretty certain the fully functional calculator was the most complex LittleBigPlanet mod around. Surely nobody could top that for sheer intricacy, could they?
Oh Internet, you spoil us. PSN user 'Cristel' has gone and implemented a basic Tic Tac Toe engine, armed only with the LBP level creator, a lot of free time and a catering sized carton of WIN.
Unless we are very much mistaken that counts as actual artificial intelligence - albeit of a simple variety. Hell, in a global thermonuclear war situation this mod could save the world, which translates as some serious modding chops.
[Thanks to Laurens Simonis for the tip]