Rupee

Rupees are small gems used as currency throughout The Legend of Zelda series, especially in the Hyrule region. They make their debut appearance in the first The Legend of Zelda. They are the equivalent to the coins in the Mario franchise.

Donkey Kong Country 3: Dixie Kong's Double Trouble!
In Donkey Kong Country 3: Dixie Kong's Double Trouble!, Bazaar mentions that Link arrived at his General Store and exchanged 500 Rupees for information. This dialogue is not included in the Game Boy Advance version.

Wario Land II
In Wario Land II, one of the hidden treasures that Wario collects is a purple Rupee.

Super Mario Galaxy
Super Mario Galaxy features the Rolling Gizmo Galaxy, in which a hidden formation of Star Bits in a Rupee shape can be seen.

Super Smash Bros. Brawl
In Super Smash Bros. Brawl, there is a sticker of a green Rupee depicting its The Legend of Zelda: Twilight Princess artwork.

Super Mario-kun
Rupees are featured in a volume of the Super Mario-kun manga.

Mario Kart 8 and Mario Kart 8 Deluxe
Rupees appear in the Hyrule Circuit course featured in the first Mario Kart 8 DLC pack, The Legend of Zelda x Mario Kart 8, which returns in the base game of Mario Kart 8 Deluxe. They replace coins from other courses, being both scattered throughout the course and obtainable from Item Boxes. They function identically to coins, giving a greater speed boost to players the more of them they have, but they play a different sound effect when collected.

Trivia

 * In Super Paper Mario, a currency called Rubees appears.