I am a bit of a sucker for new car cleaning products and have mulled over Optimum No Rinse. I am still not convinced because, like it or not, water is involved. I tend to rinse the car first with water from a watering can, then use a mitt to very gently clean using Autoglym Shampoo and Conditioner to the recommended dilution. It contains surfactants etc and thus, presumably, minimises abrasion from the dirt particles. I then rinse with about two watering cans full and dry off using an autoglym aqua dry (synthetic chamois) although I am thinking of moving to a microfiber drying towel.
Every other wash (I wash the car about fortnightly) I'll use autoglym aqua wax instead of the synthetic chamois.