Unsung, yes. But not sure the rest of the thread title applies to my nomination: Purple Chili cabs. I had one (112), couldn't get a second anywhere so sold it. Then a pair came up and I had to have them.
They never seem to appear in threads, perhaps there are just too few of them out there. They may also be too big for some in comparison to other 112s on the market, but they are light and sound absolutely wonderful. This pair are staying with me.
Oh, and they were built by Mike Walsh - @Cosmicrain maker of the very fine Zoot basses.