Yeh, AG SRP on the outside every so months then just a spray on the outside and inside with a microfibre as Rich says. I try to use as little as possible though... it does annoy me when you think it looks spotless but as soon as you are in direct sunlight there is normally a little spot I have missed. Either that or it rains straight away and have the annoying windscreen wiper marks all over the front. I have some Turtle-wax spray stuff at the moment and it is as good/ bad as any other I have used. Just don't use household glass cleaners, like my Dad tried to use, seems crap in comparisson. Alternatively vinegar is meant to be good, just don't fancy the smell!