CompuServe's failure wasn't due to a single missed opportunity so much as a collection of them, says Gregory. "I really believe [CompuServe is] an important example that reinforces a critical lesson--never stand on your heels in business."

Newspapers are dying, and by nearly all accounts (certainly, all newspaper accounts), Craigslist's fingerprints can be found all over the crime scene. People have blamed the mostly free online ad service for cutting the legs out from under classified advertising, one of the newspaper industry's cash cows.

As recently as 2005, classified ads brought more than $17.3 billion into U.S. newspapers' coffers. Since then, the use of classified ad sites like Craigslist (as well as Amazon, eBay, and Google) has more than doubled, according to the , while classified ad revenues have been halved.

If a consortium of newspapers had bought out Craigslist back in 2005, when classified ad revenues were flying high, things could be quite different today. But first they would have had to persuade Craigslist creator Craig Newmark to sell.