[V6-12v] How to get rid of that annoying sheen on the inside of windows

[The CyberPoet]

Oh, and a follow-up:

Vinegar also works to remove water spots from the outside of the car.  
If you live somewhere with hard water (esp. sprinklers spraying the  
windshield at night), a bit of vinegar (say 1/10th strength) in your  
windshield washer fluid will clear the windshield much faster and  
make your wiper blades last far longer (because calcium/lime on the  
windshield tears up the rubber edge). We use it as a post-wash rinse  
additive when washing the motorcycles for that reason...

Cheers,
=-= Marc