Sounds like the sort of weird site that would actually gain a niche following. Let users make submissions for missing entries, and you probably have an easily sustained site.
I've actually wanted to see something similar, but for films and film trailers. The Mass Effect 3 theme and two versions of Adagio in D Minor from Sunshine have been used in a lot of other media, and I'd like to know every movie, show, or trailer they've appeared in. Cloud Atlas End Title was also used in the A Monster Calls teaser. But has it appeared in any other trailers? I wanna find out!