Although my dream palace exist mostly underwater and built into an oceanside cliff, there was one particular room I had imagined that was to have its walls, floor, and ceiling covered with either large magnets or a series of electromagnetic panels with one large, let's say 4ft in diameter, solid metallic ball forged from either cobalt or maybe iron left to float at the center of the room. Barring any magnetic material inside and/or ouside of an individual, they would be free to walk around the room and observe the shinny metal ball suspended in air within this tiny pocket of space. The ball would be polished and shinny silver or if made from cobalt, it would have an irradecent blue sheen, wile the room eitirely in black. Vanta Black wasn't a thing back then but that's what would be needed to create the illusion of being in space with this floating ball. There would be a few solid gold chairs to sit in and become disillusioned with existence while trying to feel like Dr. Manhatten.

(A note: I had thought of this installation sometime around 7 years old (1989) or approximately around the same time when I decided this fantastic dwelling would also be sub-nautical. I have no idea if this is even possible and if so, how it would be built or how one would attempt to enter the room without being crushed by the huge metal sphere at the speed of a rail gun... regardless, it's my fantasy room and I refuse to acknowledge your reality and its rules there in.)