In the early 90's, many CD ROM publishers did very well. The Bureau of Electronic Publishing had a catalog with thousands of popular titles.
In the late 90's, content migrated to the web. "Content is King" was the theme of many internet conferences. Many content companies did very well--some with advertising business models, some with ecommerce, and some with subscription business models.
In the future, the same content that drove CD ROM sales and mass adoption of the internet will migrate to cell phones and other portable devices.