I made this super cool hydraulic earth mover robot that is powered entirely by water pressure. I took syringes and connected them to tubing. On the other side of the tubing is another syringe which is connected to some tongue depressors. The tongue depressors are held into formation by brads. The bucket is a small plastic cup held on by brads also. Under the platform, there are straws that are hot-glued to the bottom. There are skewers that go into the straws. The skewers have wheels on them. So when you push the "buttons," the hydraulic earth mover crane moves!!!