Calculator
The Calculator was an special item found in Paper Mario.
When Mario came back to Toad Town after getting the third Star Spirit, Skolar from Lady Bow, Mario gets surprised as the Shy Guys start to appear and attempts to do some stealing and mischief. When Mario gets near to Rowf and Rhuff’s Badge Shop, one of the Shy Guys attempt to steal the Calculator and hid it in Shy Guy's Toy Box. Apparently, Rowf and Rhuff could not run the badge shop without it because they didn’t know any math. When Mario attempts to recover the item in Shy Guy's Toy Box, he would have to defeat the Shy Guys who held the item (shown at the top of their heads) at the bottom left side area of the place Mario can access to for right now. As thanks for returning the calculator, Mario receives a I Spy Badge for a reward for giving back the item. When Mario returns to the shop later, the shop reopens.