Sugarcane

Sugar Cane is a plant that can only grow near water. Sugar Cane do not drop any seeds, but drop sugarcane which can be planted, meaning it is renewable. It grows exclusively on Dirt, Sand and after 0.8.0 in Clay blocks that are next to water. Sugarcane can then be crafted into Paper or Sugar, or replanted to yield more sugar cane. If the bottom block is broken on a fully grown sugar cane, all the blocks of the reeds are destroyed and drop, which means that sugar cane are the ideal farming plant.

Trivia

 * If the bottom block on a stack is broken then all the blocks will break.
 * Sugar cane is not a solid block and can be walked through.
 * Sugar cane does not grow away from water.
 * Sugar Canes can be crafted into Sugar and Paper.
 * If you remove water from sugar cane it will act as a BUD switch.
 * In some worlds it used to be exceptionally hard or impossible to find Sugarcane because of the non infinite worlds. However, with the launch of Update 0.9.0, it is much easier to find Sugar Cane.
 * Sugarcane grows slightly faster on sand.
 * Sugarcane can be found in the Nether Reactor too if it is not found normally on a world.
 * Sugarcane can grow up to 4 blocks high.