Consider having a command that toggles fixtures into becoming something that doesn't light up when moused over. Still subject to pickup_fixture and having those properties reset, or adding something like...
-fixture_usableon
-fixture_usableoff
This simply because many fixtures are just cosmetic, and don't necessarily need a description. Beds, carpets, tables, bookshelves used as walls, come to mind. Still breakable, pick-up-able and subject to fixture count of course.
