I once had an entire FF7 based campaign in D&D. Playing Jenova as a gigantic evil outsider, invoking meteor as an Elder Evil akin to Atropos, having limit breaks... quite fun.
I made a number of video game stuff homebrewed for D&D, most recently Metroid gear for warforged.
Love of Zelda made me bring an alternate material plane called the Dark World accessible (a blend of Link to the Past and Twilight Princess), and closely linked to the Plane of Shadow, and it's own twilit-esque race.
Shadow of the Colossus: The best epic D&D puzzle fights ever.
The campaign I'm running now has strong Soul Edge/Soul Caliber ties. Even though it's actually not the big goal, the heroes are looking for a legendary sword held by an evil knight.
Games are chock full of good stuff. Once I even made an epic spell that summoned a katamari. And yes, it grows as it rolls. Good times.