I just did a (new record) speedrun through Metroid: Confrontation yesterday with various customized things (Samus sprite, backgrounds, tiles, and music).
Now normally this would have nothing to do with Fate/stay night, except that it was my choice of custom music. A while ago when playing around with customized music in Fate/stay night, I noticed that Metroid Prime's title theme worked quite well for Fate/stay night's title, and a figured the reverse would be true. Turns out I was right, and not just for the title theme either.
Title - "Into the Night"
Overworld - "Diver ~ Diver 2" (from Realta Nua)
Kraid - "Sword of Promised Victory" (beginning only, full song is a certain spoiler-rific version exclusive to Realta Nua)
Ridley - "Emiya"