Windolene and a clean cloth to wash, followed by drying with an old newspaper. It doesn't leave any fluffy bits like a cloth or kitchen towel would, and windows / mirrors very shiny. I think I read something about it relating to the ink, but no idea if that is true.
I am hoping to have a bit of a Spring Clean over Easter and my windows are in particular need of some TLC both inside and out. Which products and methods would you recommend to get the best results with the least effort??!