[quote=nautilusmp]
What are Ominous Floating Block of Doom (tm) and Ominous Floating Door of Doom (tm)? Some sort of snack? (sorry for not being funny)
[/quote]

GM's hideout in the sky. It used to be a very awkward-looking black box, but then he shrunk the size of it (on the outside, anyway) so that, yes, it's mostly just a door now.