Its actually quite creepy we think. Each of the 144 Furbies has two dedicated Arduino boards to control the Furby and also add some additional synthesis - as he said, it was extremely difficult to control the Furbies with enough granularity to make them actually sing, just using external control, so a new synthesis method was conceived: Formant Furby Formant Synthesis. A labour of love most definitely.
Two (well, three) new products from Verbos
Highly configurable Eurorack module