>>105116552The Changing Chopsticks, which had the ability to shrink anything down to the size of a grain of rice. Jack used it to sneak into the vault undetected while his Kimiko robot was fighting the monks. He then changed back to normal size, stole all the Wu, and then flew back out tiny so they wouldn’t notice him.
Prior to that, the chopsticks had been considered the most useless Wu that a person could have, because it wasn’t really useful for combat.
After that, it became one of their mainstays, used primarily to shrink things down for easy transport.