Very cool.
My landlord made a self watering garden which has helped his veggies grow lovely and strong. He turns the water on for an hour per day then turns it off when it is done. He used more of a tube than a pvc piping system though. Anyway really cool!

Also a friend of mine uses a trout tank and a water system that uses the fertilizer from the trout poop and such water his garden/veggies inside his greenhouse he built and it was really really interesting!!! He is a fish expert (used to teach at a college about marine life) so it is cool he used fish to incorporate his garden.

Great post! I love learning what people do like this.