I just started an Arduino based incubator project. I have got the basics done - I have a working set of hardware/program to measure temperature, humidity, and control a relay to turn a heat source (light bulb) on and off. The temp, humidity, and time are displayed on a 4 line LCD. I have had it running for several days and it is working great. Now I am thinking about the automatic egg turning. I have a second board with a working stepper motor that can push the eggs to "roll" the eggs once per hour (or whatever I program the interval to be). Not sure if the stepper motor will have enough torque to get the job done (it is a cheap one). I plan to use a Styrofoam cooler to hold the eggs and minimize the heat loss. Any suggestions on the auto egg turner? The relay can take almost any voltage (including 110 and 220 AC or most DC voltages). Happy to share the code and parts list.