I made some progress with the wax on this one too. I thought I had cleaned it, if not thoroughly, at least decently, but the cloth I used for waxing was black as sin by the time I was done. And the greenish Lovecraftian fungus-mucus that stained the cloth when I waxed the keys (again, I thought I had cleaned them pretty good, they looked clean to the naked eye!) showed me that some kinds of filth can survive a soap-soaked attack, even if you rub the area where it has gathered. I wonder how many computer keyboards are as fun or rewarding to clean as the keys that give your soul a voice?