California Doubling: Inverted. The only Black Mirror episodes filmed where they take place are the ones set in the UK; Brooker says he has a policy of filming the US-based episodes in other countries because the cost of US location filming is just too high for a UK-based production.
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Celebrity Paradox: The first episode mentions Downton Abbey — many actors from that show (including two of the main cast) appear in large roles in Black Mirror. One of them, Allen Leech, even appears in that very episode.
Channel Hop: The series began on UK tv station Channel 4, airing Series 1, 2 and White Christmas, before the show was bought by Netflix to be one of their full original shows.
Promoted Fanboy: Butcher Billy created fan art of the show that became popular online before Netflix hired him, putting his artwork on the cover of the San Junipero album, and in the episode Black Museum, as well as having him do more original work for the episode USS Callister. He even tweeted about it. He creates art for use in other Netflix shows now, and has a pretty healthy following from it all through Black Mirror.