Answer: The Legend of Zelda: Phantom Hourglass

While it’s not uncommon for a game maker to include self-referential nods in their games (Nintendo put a Wii console in their popular DS game, Pokemon Diamond, for example), it’s a rare treat to find a self-referential nod that references the device you’re actually playing on.

In The Legend of Zelda: Phantom Hourglass, not only is there a nod to a Nintendo device, but the Easter Egg is the actual device you’re playing the game on: the Nintendo DS. Furthermore, it’s not a tiny reference either, Dee Ess Island is a completely accessible level that you can visit with your ship and roam around on.