I use one of those lint free clothes that is made to clean your sunglasses. It came with my Oakley sunglasses when I bought them, but I'm sure you can pick them up everywhere for a decent price...works like a charm
2005 Black Chevy Impala
Current Status: Installed in Vehicle/Testing 75%
This is most important.Make sure you use a Micro Fiber towel, 100%cotton you can get them at any auto place that sells detailing supplies.
I use that kind of towel and windex, not no-name stuff actual Windex. Crapped my pants the first time I did it and used a paper towel and no-name glass cleaner. The screen was foggy and looked like I scratched it from the paper towel. Ran out got a Micro Fiber towel and REAL Windex as suggested on these boards and re-did it, it was not scratches, only streaks (thank god).
Takes 2 seconds to clean and looks good, the screen looks like new everytime I do it.
2008 350z GT Installed since April 22nd 2011 - Worklog 2000 Protege Installed Since April 2, 2005 - Intel D201GLY|Fusion Brain|ODBPros ODBII|Engenius|GPS Rikaline|Powermate|Motorized Lilli
I've had really good luck with those pledge wipes for electronics....they won't harm the coatings, and so long as you're using a new wipe, they won't leave particulates behind. They come in a blue plastic pouch. The last time I was at a meet, I cleaned the screen with them, and even in the direct sunlight of the park we were at, a guy asked me if it was one of those transreflective screens. It isn't (Xenarc), but having a clean screen makes a lot of difference (although doesn't improve inherent characteristics of the screen, just allows it to be at its best.)
I have too much time and too little aggravation in my life, so I built a carPC. ;)