Aquarius is a large robot that I built for use in greenhouses where each plant needs to be hand watered several times a day. Ive been meaning to post it here for a while, but things keep getting busier. :)
This robot was born out of a cost saving brain storming session at my old job where we evaluated transgenic plants for efficacy against insects in a high throughput discovery pipeline in a large greenhouse system. It was typical for our group to have several thousand transgenic plants in our system at any particular time. Because these were newly transformed plants, they were very susceptible to desiccation, and they were very valuable so extra care had to be given to make sure they were given the correct amount of water. Aquarius was built and demonstrated that it was capable of quickly and accurately measuring the soil moisture in each pot, calculate the correct amount of water to give the plant and then dispense that amount of water. Aquarius did all of this simultaneously on both sides without slowing down.
Of course the thing that we find the most important is that Aquarius uses two Propeller chips for its main brains :)