BoJack Horseman (season 2, episode 8) called Let's Find Out. The new season is now available on Netflix. He appears in this episode as himself: celebrity guest in a game show.
Update: 19th September 2015. How Daniel got involved. source: Yahoo
The Harry Potter star didn’t appear in early drafts of the script — a generic “Major Celebrity” was written in as a placeholder instead — but when word got back to the staff that Radcliffe was a fan, Bob-Waksberg immediately acted on that intel and secured the actor’s involvement. “Daniel had a great time doing it. He recorded it over the phone from England. And at the end, he told me ‘I’ve seen every version of a Harry Potter joke and you guys wrote my favorite.’ He meant it as a compliment, but I was like ‘Every version? Oh man, what number are we?’”A scene:
Host: "Bojack, for all the marbles"
"Which famous actor played the titular role in the popular Harry Potter film franchise?"
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