My R32 doesn't have a rear wiper Thanks to it being a GTE model (pretty much bottom of the range). I like it better without.
I also have the option front 'auto-spoiler', although this didn't come with the car. I sourced it to buy intentionally and ended up buying one with the motors for $30. I never hooked up the motors though, I just fitted it straight to the front bar.
I also have the factory option weather visors that go above the doors, got these from Japanese Yahoo Auctions. These for 4dr are so hard to find.
For rare/unusual modifications I have a genuine Nismo cup holder, nismo leather gear knob but not just any nismo gear knob, it's got the old style logo on it. My Recaro you could say is a rare model too, it's the Recaro SR3 'trail' model.
I got 17" 5 stud Formula Mesh rims which are also very rare to come across.
I love owning unique/rare/unusual items on my car.