These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: The Third Policeman
Cargo Ship: The narrator has an extremely sensual relationship with a woman's bicycle Sergeant Pluck keeps locked up in the cell. This was completely intentional on the part of O'Brien. It also serves as a Brick Joke for Sergeant Pluck's concerns about bicycles becoming sentient.
Colbert Bump: The novel was featured prominently in an episode of LOST: over the following three weeks following the episode's initial airing, sales of it equalled what they had been in the preceding six years.
Ho Yay: between the main character and John Divney.
Vindicated by History: O'Brien was unable to find a publisher for the book in his lifetime; he reused and refined some elements of the book for his last novel The Dalkey Archive, but gave up trying to publish The Third Policeman — in fact, he was so ashamed of his failure that he claimed to have lost the manuscript whenever anyone asked him about it. It was only after his death that it was published and quickly hailed as a masterpiece.