Here are a bunch, Teia, and I haven't heard/hadn't heard a lot of them.
List of slang terms for police officers - Wikipedia, the free encyclopedia
Often we get questions from students about what structure can/must be used in certain circumstances. Sometimes, situations arise where two or more can be used. It all depends on the focus of the speaker. Here is one such scenario. Students should be aware that the context, the focus is crucial to deciding what structure is used /can be used.
I haven't heard = a focus on recently viewing the list and expressing that "up to now", the time of writing this, I haven't heard some of them.
I hadn't heard = a focus on the past action of viewing the list and having closed that window, I'm writing this thinking, "until I looked at that list".