Wired: “Free! Why $0.00 Is The Future of Business“:

Zero marginal cost
What’s free: things that can be distributed without an appreciable cost to anyone. Free to whom: everyone.
This describes nothing so well as online music. Between digital reproduction and peer-to-peer distribution, the real cost of distributing music has truly hit bottom. This is a case where the product has become free because of sheer economic gravity, with or without a business model. That force is so powerful that laws, guilt trips, DRM, and every other barrier to piracy the labels can think of have failed. Some artists give away their music online as a way of marketing concerts, merchandise, licensing, and other paid fare. But others have simply accepted that, for them, music is not a moneymaking business. It’s something they do for other reasons, from fun to creative expression. Which, of course, has always been true for most musicians anyway.

When reading this article about the distribution of low marginal cost goods and services, consider the impact of ‘free’ on (1) intellectual property protection; and (2) delivery of legal services.
I note that in my practice that because of technology, there are certain activities, such as dead-hit searches, that, under certain circumstances, I no longer charge for (or subsume under set fees for other activities).