U2'S BIG (RED) DOWNLOAD

How do you move between 2.5 million and 3 million singles (depending on varying reports) in two days? Well, here's one way: Start with a new song by a superstar band. Make it free. Advertise it on the largest TV platform in the known universe. Then add a corporate donation to a worthy cause, so consumers can feel they're doing good just by grabbing it.

U2's "Invisible," offered gratis on iTunes at Super Bowl time as a partnership between the band, the downloading emporium, Bank of America, and (RED), generated a fat check for the latter global charity (which fights AIDS, tuberculosis and malaria worldwide) courtesy of B of A, which committed to contributing $1 for every click until the promotion ended Monday at midnight (the financial behemoth says in a release that it exceeded its original pledge by $1 million). More than 1 million downloads reportedly happened in the hour after the airing of the Super Bowl ad touting the campaign.

This feat makes "Invisible" the largest free download ever for Universal Music; the average traffic for a free track on iTunes is in the neighborhood of 400k.

"Thanks to the extraordinary generosity of U2 and Bank of America, in just 36 hours (RED) has generated more than $3 million for the global fund," the nonprofit's CEO, Deborah Dugan. "These are much-needed funds for the fight to end the AIDS pandemic in our lifetime and to get closer to the goal of eliminating mother-to-child transmission of HIV by 2015." The organization has raised more than $250 million to date in the fight against these pernicious diseases.

The U2 song is no longer free, but all revenue from its sale will continue to go to (RED). The band's new Interscope album, with Danger Mouse behind the boards, is still in progress; the band drops a few choice thoughts about it here.