[I have a copy of Mickey Mouse Museum. It probably isn't a "must have", but it is "nice to have".
I was pleasantly surprised by the latest grocery store checkout magazine. It does have useful information including brief interviews with some of the Italian Mickey comic book artists and the newest voice of Mickey Mouse. There are a couple of photos I had not seen, and some artwork from an unproduced short: "Morgan's Ghost". There is a Glen Keane drawing of a worried Mickey looking at Ratigan, a reproduction of a newspaper cartoon about Walt's death, and some pre-production art from a couple of released shorts.]