Langton's ant
From Tardis Wiki, the free Doctor Who reference
Langton's ant was a two-dimensional, four stage simulation with simple rules that resulted in complex patterns. Ro-Jedda used the principle with Deliverables to gain control of the Rift (AUDIO: Zero Hour) after Bilis Manger disrupted it to send a message (AUDIO: A Kill to a View) to God. (AUDIO: Herald of the Dawn)
Orr learnt of the simulation as her first human owner liked them to talk about such things whilst wearing bunny ears. St John Colchester was also aware of it and described it as being "cosmic knitting". (AUDIO: Zero Hour)
