Algodoo

Inspired by (I forget who)'s artificial life and darkphenix's Auto-Eater.

Just press play and let it run. The lasers that you will see are the organs.
The white laser is both an organ and a neuron, providing its sense of sight.

Upon hitting a food pellet, the white laser will alert the brain (the pink blob in the middle).

The small green laser on the front is a neuron, and it is allowed to pass once the organ in front of it (that green block behind that other green block) senses food. It tells the brain that it successfully consumed food. If the machine doesn't find food after 12 seconds, the neuron in the back will look again for food.

The small bar looking thing in the front with a laser in it is purely an organ. It traps the food. Think of it as an asophagus - it "swallows" the food into its
digestive system.

Overall this thing was a load of fun to build, and I plan to build another in the future. Maybe one that turns its waste back into food.