Years before Facebook or Google undertook a similar mission, AOL's business team also began coming up with ways to cash in on the "big data" they had collected: that is, the addresses, phone numbers, and credit card numbers of millions of users. The walled garden, by its nature, was already giving companies direct access to users and some of their information; now AOL also began allowing them, for instance, to insert ads into emails (making the service, in effect, a spammer of its own users). But there were more audacious plans still. AOL sold its users' mailing addresses to direct mail companies. It was going to sell the phone numbers to telemarketers as well, shamelessly describing these maneuvers in its terms of service as a membership benefit. Alas, an inadvertent leak of the plan prompted a user revolt and the telemarketing part was abandoned.

Tim Wu, The Attention Merchants, loc. 737