and distilled water
Dry ones to clean the screen or general wipe downs, and a dab of distilled water - screen looks brand new, same with the keys. I would never go back to iklear or gimmicky stuff like that, I'd avoid eyeglass cleaner unless it's distilled water/isopropyl
I use the stuff I use to clean my eyeglasses and the cloth too. Spray it on the cloth and with almost no pressure on the screen, drag the cloth across. I find blowing gently on the screen helps the liquid evaporate faster and reduces the smudge lines.