Bottomless Coin Sack

The Bottomless Coin Sack is a magical item in Wario Land: Shake It! that holds an infinite amount of coins and whenever shaken, will summon the coins out of the coin sack. The Bottomless Coin Sack resides in the Shake Dimension and is basically the center of the Shake Dimension's life. The Bottomless Coin Sack is stolen by the pirate known as the Shake King. In the first cutscene, the Shake King presents this precious artifact, and the Bandineros (and a few Shortfuses) around him hop in happiness. The Shake King also said it is a legendary treasure. Captain Syrup, the female pirate, wants to possess this item for herself. However, she doesn't want to do any of the dirty work herself, so she "hires" Wario.

Trivia

 * Coincidentally, there is a similar item in Super Mario RPG: Legend of the Seven Stars, which is a golden treasure chest created by a Magikoopa (possibly Kamek), and it contains an infinite amount of coins.