The old switch plates....maybe I'm nuts, but I think they're cool.
The glass door knobs on all the interior doors....love them!!
There's even a skeleton key to unlock all of them.
They have wavy spots in the glass and at either side have ropes attached to a pulley thing that helps them slide up and down.
Half of them don't open, and of the other half that do, it's always questionable whether they'll close again. But I think they're so cool.
And the ridiculously pretty view out of them has got to be my favorite thing.