In October 2007, the English rock band Radiohead enhanced its already enviable avant-garde credibility by releasing its seventh album, In Rainbows, online. Fans willing to offer up their names and e-mail addresses--or at least, fake names and fake e-mail address--could pay what they chose for the album, even downloading it for free. The band, and the "tip jar" business model it had adopted, were the talk of the music press and the blogosphere for weeks.

Just days after the release, ­the site Gigwise.com, citing an unnamed source "close to the band," claimed that 1.2 million copies of the album had already been downloaded. At about the same time, a survey by a British company called Record of the Day pegged the average price paid at about $8. But Billboard, the U.S. music industry's leading trade magazine, estimated the number of downloads at closer to 400,000, although it accepted the $8 average. And ComScore, a consumer research company based in Reston, VA, that collects data on the online behavior of a representative two million people worldwide, calculated that in the first 29 days of October, about 1.2 million people visited the Radiohead site. Although a "significant percentage" of them downloaded the album, ComScore said, the average payment was $2.26.