If you are getting a bit sick of all the microcontroller and complex IC projects this Line Following Breadboard Tank will be a nice break. There is no microcontroller in this puppy, in fact all you need to do if you want to make your own is buy the parts (or search for them in your junk box) and start building. The schematics and complete build instructions are provided.
“The purpose of this project is to build a device that can sense the difference between black and white color so that the robot can follow a black line on a sheet of white paper. When the line-following mini-tank is built, the real fun can begin. I built a few simple tracks to test it out on at first like straight lines. Normal paper and a sharpee felt pen work very well for making courses.”