I call it the bootstika because it looks like boots... around a ... swastika... (not intentional, but handy anyway).
code:
#################################
#.#....#.#....#...#.#....#.#....#
#.####.#.####.#...#.####.#.####.#
#....#.#....#.#...#....#.#....#.#
####+#+####+#+#...####+#+####+#+#
#...............................#
#+#+####+#+####...#+#+####+#+####
#.#....#.#....#...#.#....#.#....#
#.####.#.####.#...#.####.#.####.#
#....#.#....#.#...#....#.#....#.#
###############...###############
I had a dwarf whose home intersected a gold vein get a Royal Bedroom just because the walls were crudely engraved and he had a bed, coffer, cabinet, and door.
I have seen rooms in fortresses of mine hit over $3000, and they were just engraved chalk walls with various furniture.