Here's a way to eliminate most flats by a simple procedure. Poke a pin into each crack of your tires about once a month (for an average 100 miles a week of riding). Most cracks will have a tiny chip of glass, sometimes metal, that will come out or pop out as you move the pin around inside the crack (unless you already got them out at a previous check). What happens is that as you ride, the glass is driven deeper and deeper, and the crack size increases, until you either take the glass out or you get a flat. (Omit this procedure for ATB tires, the rubber is so thick you won't get a flat from glass chips.)
Also see: list of bicycle articles.