What is the fine-grained topic of the following text: The constant stream of endearing tunes is so reminiscent of soundtracks gone by that any sentimentalist, or committed hipster, will no doubt get the sudden urge to root through their old cartridges and further indulge in the kind of nostalgic atmosphere that Null Divide+ does so well to invoke. Only return the topic.
Nostalgic atmosphere in Null Divide+ game soundtracks