I use eyeglass cleaner wipes and a non-static rag (microfibre)
Be careful with windex or alcohol-based cleaners. Over time, they will wear away the finish (not the glass).
I've been using windex and a microfiber cloth, never had any issues, and cleans really well..
I'd really be careful about anything with ammonia in it. We know stuff can get from outside the machine to under the glass (insect stories). I'd worry about the ammonia vapors doing something to the actual LCD panel. I use a cleaner safe for non-glass LCDs (Monster Cable).
AND, as most probably know..... cleaner goes on the microfiber cloth, NEVER on the screen.