Certain emulsions, particularly black and white, age very slowly. I buy my Neopan 1600 from eBay, a couple years expired, generally for about $2.75 per roll. I think it looks the same as it did when I used to buy it fresh. Any other films I get from eBay are unusual finds (APX 100 for $2.35 per roll) or anything that's about 40% off the cost from B&H or Adorama (160S expired 9/09 for $2.60, purchased before the expiration date). I'm comparing auction prices including shipping against B&H/Adorama prices including tax. For the most part though, I'm happy to buy from my local shops.