Sebin Saji—a maker in Kerala, India—built the world's smallest washing machine and it actually runs a full cycle of wash, rinse, and spin. Demo video below. Measuring 1.28" x 1.32" x 1.52", it weighs about as much as a AA battery. (It's powered by two of them in an external battery pack.)
According to Guinness World Records, Sebin made the device specifically to land a Guinness World Record. He has now achieved his goal.
The machine would be ideal for laundering your belly button lint.
Previously:
• Bella, a 14-year-old cat, sets new Guinness World Record for loudest purr
• This woman's terrific tongue holds a world record (video)
• Watch the world's highest bungee jump by a car