So of course this sort of topic doesn't really apply to those whose like to brag about the eclecticism of their music collection. Certainly most of us favor a handful of genres that constitute most of our collection, and there must be a few artists/albums in your collection that cause onlookers to scratch their heads.
Prince - Of course I've own other "random" albums, but in a collection dominated by hard rock/metal and classic/progressive rock, the lengthy stop-gap of Prince albums certainly stands out (everything from his debut to GRAFFITI BRIDGE, which is like a dozen albums or something). Of course, Prince experimented with so many different genres of music, that I like to argue that his own eclecticism was "progressive" (not to mention being a very talented guitarist) but that's just me trying to explain myself to my metalhead friends when Prince comes on in the car.
Anyway, DIRTY MIND is certainly one of the best albums ever.