Riding the proliferation of cheap round displays from smart watch development, building eyes is the obvious next step. I threw these eyes together for a few masks a friend had sculpted for a party and I've been told that others would like to use it for their project. Total BOM cost per pair of eyes with controller is on the order of $20 so your next project should probably have eyes. The software is simple, a 220x220px window moved over a 300x300px image to simulate looking around. Blinking is white at 45 degrees to simulate the crow's nictitating membrane. If you're building many it's trivial to add synchronous blinking using the ESP-NOW protocol or similar. There was also the plan to add a photodiode to have the eyes dilate under bright light. The dilation code is in the random display section. The small images which show up randomly are meant to add an element of whimsy but it's easy enough to strip it down to just the eyes looking around. Github has the build guide