I received this post from Adafruit that I thought might be of interests to some community members. The post does a teardown of a commercial Halloween product using what appears to be open source technology. https://learn.adafruit.com/eye-shootout-contrasting-open-source-and-big-retail-electronics?view=all
I wanted a big boy toy for Christmas one year, so I included a pair of Adafruit eyes on Santa's list. I would recommend the product. The learning resource provided slonr is what encourages me to keep going back to Adafruit.