I use a "pledge" type product for quickie touch-ups but mostly for the windshield where it is excels in putting a thin coating that seems to remove very fine scratches and helps to keep the shield clean.
I also use those handy automotive spray waxes (Meguires, i.e.). They are great for almost anything that painted or metal. I found some with Canuba wax that I prefer. Hey, it's real wax. It's very easy to use, non-abrasive and I use it on chrome too.