The Zen Gardener is a robot that rakes a Zen garden. It was built to immediately beg the question should it exist? The provocation is just because there is a technology, should one deploy the technology? Isn't a core part of a Zen garden the act of raking the garden yourself? However as technology becomes cheaper things like this can exist, and in this case do exist. There it is, in the video. Feel free to give your own thoughts about this philosophical question in comments.