Books upgrade
I was looking at Programming ASP.NET, Second Edition on Amazon and suddenly the question came up:
Why do we always expect software vendors to offer upgrades for their products but no one expects that for books? Is there some economical rationale I'm missing? How cool would it be to walk into a bookstore holding the first edition and to hear "Oh, yes, sir, this mighty book you've got in your hands qualifies you for an upgrade discount of 40%".