Putting plastic over your windows is just one of may ways to conserve energy this winter. Some people think it's tacky. I think it's tackier to waste energy. And nothing is tacky about saving money. You can save up to 20 dollars per window per winter. (depending on furnace type and locale) That's a big heap of money. You could roll around in that money, but you'd be better off leaving it in your bank account.
3M is reported to make some of the best window film around. The 3M company even provides you with an energy-savings calculator so you can find out how much money you'd save with their window film.