FLUDD is the watering cannon that Mario uses in the video game "Super Mario Sunshine" for the Nintendo GameCube. Created by Professor E. Gadd, FLUDD (short for Flash Liquidizer Ultra Dousing Device) is Mario's primary tool for saving Delfino Island from evil. Mario uses his FLUDD to hurt enemies, wash off graffiti, and glide him across gaps to safety.

The FLUDD has four variations:

- a spray nozzle used to wash off graffiti, hurt enemies, and control certain levers

- a hover nozzle used to temporarily glide Mario across gaps and access seemingly unreachable areas

- a rocket nozzle used to shoot Mario high into the air to reach platforms inaccessible by any kind of jump

- and a boost nozzle that allows Mario to shoot forward on both ground and in water at an immense speed, sometimes fast enough to break barriers. Unlike the other FLUDD variations, the boost nozzle can be used as long as Mario has water in his FLUDD, meaning he could use it infinitely when boosting in water.

Mario can have as many as two of the nozzles equipped at all times, but the spray nozzle must always be one of them. He can switch nozzles at the touch of a button, and can change nozzles by finding color-coded 'E. Gadd' boxes that correspond to each nozzle.