“No new hobbies, equipment, games, or books are allowed during this year. Instead, you have to find the value in what you already own or what you’ve already started. You improve skills rather than learning new ones. You consume media you’ve already stockpiled instead of acquiring more.”
I’m not sure about doing this for a full year, but it certainly seems like doing it for a month could produce some interesting results.
Raptitude introduces the concept of a depth year, in which you commit to not start anything new or acquire any possessions you don’t need.
The idea is to focus on a carefully curated set of interests as opposed to shifting your attention from one momentary infatuation to the next.