For this you can thank Hammacher Schlemmer : Modeled after the most well-known astromech droid in the galaxy, this R2-D2 holds a 1 3/4-gallon aquarium tank in his central compartment, ideal for a small freshwater family of goldfish, gouramis, or tetras. The domed head rotates with any vocal command you issue and he utters his familiar “bleeps” from the Star Wars movies. It’s $130, twenty inches tall, and plugs into the mains. It even comes with a two-sided cardboard insert so that your fishes can enjoy scenes from the movie. [HS via Wired ]

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R2-D2 Aquarium