You hear the Oot store music or Malo Mart theme in your head when you walk into a convinient store.
You hear the Zelda chime when you figure out a math problem
When youn just caught any of the Legendary Flying types in pokemon (Ho-oh, Zapdos etc) & name it Loftwing.
When you look at Jabu Jabu in OoT & think: A wild Wailord appeared!!!...wait thats if you played too much Pokemon...