I just had the oil changed in my Dodge and the dealer filled the windshield washer fluid. Ever since, it has the most awful smell (smells like the old style straight anti-freeze as memory and my nose serve me).... regardless, I went back to the dealer just to make sure they didn't fill with the wrong bottle -- nope -- the current stuff they have smells to high heaven. Didn't think about it until I saw Brad's post above. May it be something so trivial and easy to find!!!
On edit, I did ask if they knew why the company made it smell so bad, dealer had no real answer. Do know that my wife doesn't want to ride with me in the truck right now though - says it stinks so bad it makes her sick. That is not good!!